OFS23 General Schedule at a Glance:

Hours Sunday 1 Monday 2 Tuesday 3 Wednesday 4 Thursday 5 Friday 6

08:00-08:30 Regist. open (up to12:00)

Regist. open (up to12:00) Regist. open (up to12:00) Regist. open (up to12:00)

08:30-09:00 Plenary talk II Plenary talk III

09:00-09:30 Opening Remarks S12: Invited paper 10

09:30-10:00 Opening Plenary talk 4 oral talks 4 oral talks 4 oral talks

10:00-10:30

10:30-11:00 Coffee Break Coffee Break Coffee Break Coffee Break

11:00-11:30

Registration open

S1: Invited paper 1 S5: Invited paper 4 S9: Invited paper 7 6 oral talks (postdeadline) 11:30-12:00

4 oral talks 4 oral talks 4 oral talks 12:00-12:30

Closing Re. 12:15-13:00

12:30-14:00

Lunch 12:30-14:00 Lunch 12:30-14:00 Lunch 12:30-14:00

Lunch 13:00-14:30 14:00-14:30

Special Session I Special Session II

(2invited talks)

S2: Invited paper 2 S6: Invited paper 5 S10: Invited paper 8

14:30-15:00 4 oral talks 4 oral talks 4 oral talks

15:00-15:30

15:30-16:00 Coffee Break Coffee Break Coffee Break Coffee Break

16:00-16:30 Registration open

Special Session III (5 invited talks)

S3: Invited paper 3 S7: Invited paper 6 S11: Invited paper 9

16:30-17:00 2 oral talks 2 oral talks 2 oral talks

17:00-18:30

Posters I and refreshments

Posters II and refreshments

Posters III and refreshments

18:30-19:00

19:00-20:30

Cantabria Folk Dance Show WELCOME

RECEPTION Conference TOUR

Gala Dinner

Welcome live music concert

20:30-21:00

21:00-21:30

Flamenco Show

Awards Ceremony

21:30-22:00

“De pinchos por

Santander” Live Worldwide Music Concert

22:00-22:30

Disclaimer The University of Cantabria and their approved representatives (Photonics Engineering Group of the University of

Cantabria and FLTQ) cannot take responsibility for any accident, loss or damage to participants or to their property

during the conference.

Welcome The International Conference on Optical Fibre Sensors (OFS) is acknowledged as the world's leading interdisciplinary conference on all topics related to photonic sensing (sensing Using Light) with an emphasis on those enabled by optical waveguides and especially by optical fibres.

OFS provides a vibrant forum for reporting the latest advances in fibre-optic and photonic sensing technologies and related devices. The conference has also fostered the exchange of knowledge and ideas within the research and industrial communities. The conference series is held every eighteen months, in rotation between the Americas, Europe, and Asia and the Pacific.

In 2014, OFS will be held in Spain for the first time. OFS23 will be held from Monday 2nd to Friday 6th June in Santander, Cantabria. The conference has now passed its three decades and shows every sign of continuing to grow in importance and popularity. OFS conference series has undergone considerable evolution and healthy growth over the years, reaching now its 23rd occasion, which can already be considered a success in respect of the number of submitted contributions (535), an absolute record in the history of the Conference. During OFS23, a total of 401 papers will be presented and discussed, 68 in oral and 333 in poster format. After a first review process (with 4 reviews per paper) 375 high quality papers from 35 countries have been accepted. In addition, another 6 postdealine papers will be accepted for presentation at OFS23 in a second review process. It must be also remarked that the Conference attendees will have the opportunity to enjoy 20 invited presentations from worldwide leading researchers, with 3 of them as plenary talks of one hour delivered by highly renowned scientists from leading Institutions. OFS is only ever as good as the quality of the papers presented, and we are grateful to all of our authors for their excellent contributions. Prof. Alan Rogers has been a leading figure in our subject since its inception, and his recent death is a sad loss to the community. OFS23 will recognise his generous and outstanding contributions in a special session (Tribute to Alan Rogers) and by naming one of the Best Student Paper Awards after him: the Alan Rogers Best Student Paper Award on distributed sensors and sensor networks. We are especially appreciative of the support of companies and institutions that have generously sponsored the Conference, representing a key contribution enabling us to achieve the high quality to which we have aspired for OFS23. We are grateful to all staff of the conference office for their hard work and enthusiasm, in particular we would like to thank Jesus Mirapeix, Ana Maria Ruiz, and Jose Valdiande at the Photonics Engineering Group and Mercedes Elg at the SPIE for their effective and indefatigable dedication. We are delighted to welcome you to the city of Santander and to wish you an enjoyable and successful Conference.

Jose Miguel López-Higuera Julian Jones Manuel López-Amo Jose Luis Santos

CONFERENCE CHAIRS

General Chair Prof. José Miguel López-Higuera, University of Cantabria, Spain Co-Chair Prof. Julian Jones, Heriot Watt University, UK Technical Co-Chairs Prof. Manuel López-Amo, Public University of Navarra, Spain Prof. Jose L. Santos, University of Porto, Portugal

SESSION CHAIRS

Dr. Alan D. Kersey, CiDRA (United States) Prof. Li-Bo Yuan, Harbin Engineering Univ. (China) Prof. Moshe Tur, Tel Aviv Univ. (Israel) Prof. Prof. David J. Webb, Aston Univ. (United Kingdom) Prof. Reinhardt Willsch, Institut für Photonische Technologien e.V. (Germany) Prof. Michel J. Digonnet, Stanford Univ. (United States) Dr. Robert A. Lieberman, Intelligent Optical Systems, Inc. (United States) Prof. David Jackson, University of Kent, UK Prof. Brian Culshaw, Strachide Univ. (United Kinddom) Prof. Young-Geun Han, Hanyang Univ. (Korea, Republic of) Prof. Kazuo Hotate, The Univ. of Tokyo (Japan) Prof. Xiaoyi Bao, Univ. of Ottawa (Canada) Prof. Yun-Jiang Rao (China) Prof. Gabriele Bolognini, Consiglio Nazionale delle Ricerche (Italy) Prof. Miguel González-Herráez, Univ. de Alcalá (Spain) Prof. Zuyuan He, Shanghai Jiao Tong Univ. (China) Prof. Wei Jin, The Hong Kong Polytechnic Univ. (Hong Kong, China) Prof. Leszek R. Jaroszewicz, Military University of Technology (Poland) Prof. Hypolito J. Kalinowski, Univ. Tecnológica Federal do Paraná (Brazil) Dr. Pierre G. Ferdinand, Commissariat à l'Énergie Atomique (France) Prof. Wojtek J. Bock, Univ. du Québec en Outaouais (Canada) Prof. Hideaki Murayama, The Univ. of Tokyo (Japan) Prof. Minghong Yang; Wuhan University of Technology, China Dr. Gilberto Brambilla, Univ. of Southampton (United Kingdom) Prof. John Canning, The Univ. of Sydney (Australia) Prof. José Luís Fabris, Federal University of Technology, Paraná (Brazil).

CONFERENCE COMMITTEES

International Steering Committee Prof. Wojtek J. Bock; Université du Québec in Outaouais, Canada Prof. John Canning; The University of Sydney, Australia Prof. Youngjoo Chung; Gwangju Institute of Science and Technology (GIST), South Korea Prof. Wei Jin; The Hong Kong Polytechnic University, China Prof. Julian Jones; Heriot-Watt University, UK Prof. Hypolito José Kalinowski; Federal University of Technology, Paraná Prof. Jose M. Lopez-Higuera; University of Cantabria, Spain Dr. Alexis Mendez; MCH Engineering LLC, USA Dr. Glen A Sanders; Honeywell International, USA Prof. Nobuaki Takahashi; National Defense Academy, Japan Prof. Luc Thévenaz; EPFL Swiss Federal Institute of Technology, Switzerland Prof. Reinhardt Willsch; Institute of Photonic Technology (IPHT) Jena, Germany

Technical Program Committee Prof. Jacques Albert; Carleton University, Canada Dr.Chris Baldwin; Weatherford, USA Prof. Ole Bang; Technical University of Denmark, Denmark Prof. Xiaoyi Bao; University of Ottawa, Canada Prof. Francis Berghmans; Vrije Universiteit Brussel, Belgium Dr. Gabriele Bolognini; IMM Institute, National Research Council (CNR), Italy Dr. Gilberto Brambilla; Optoelectronics Research Centre University of Southampton, UK Dr. Clay Kirkendall; Naval Research Lab, USA Prof. Stephen Collins; Victoria University, Australia Dr. Geoffrey A Cranch; Naval Research Laboratory, USA Prof. Michel Digonnet; Stanford University, California Prof. Wolfgang Ecke; IPHT Jena, Germany Prof. Gerald Farrell; Dublin Institute of Technology, Ireland Dr. Pierre Ferdinand; CEA LIST, France Prof. José Luís Fabris; Federal University of Technology, Paraná – Brazil Prof. Miguel Gonzalez-Herraez; University de Alcalá, Spain Prof. Young-Geun Han; Hanyang University, Korea Prof. Zuyuan He; Shanghai Jiao Tong University, China Dr. Juan Hernandez-Cordero; Universidad Nacional Autónoma de México, México Prof. Leszek R. Jaroszewicz; Military University of Technology, Poland Dr. Robert A. Liebermann; Intelligent Optical Systems (IOS), USA Prof. Manuel Lopez-Amo; Universidad Pública de Navarra, Spain Prof. Cicero Martelli; Federal University of Technology, Brazil Prof. Robert McLaughlin; University of Western Australia Dr. Edgar A. Mendoza; Redondo Optics Inc., USA Prof. Hideaki Murayama; The University of Tokyo, Japan Dr. Kazuhide Nakajima; NTT Corporation, Japan Prof. Kyunghwan Oh; Yonsei University, Korea Prof. Bishnu Pal; Indian Institute of Technology Delhi, India Prof. Gary R. Pickrell; Centre for Photonics Technology, USA Prof. Jürgen Popp; Friedrich-Schiller University Jena, Germany Prof. Yun-Jiang Rao; University of Electronic Science and Technology of China, China Dr. Takanori Saitoh; ANRITSU DEVICES CO., LTD., Japan Mr. Akira Sakamoto; Fujikura Ltd., Japan Prof. José Luís Santos; University of Porto, Portugal Prof. Satoshi Tanaka; National Defense Academy, Japan Prof. Pedro Torres Trujillo; Universidad Nacional de Colombia, Sede Medellín, Colombia Prof. Moshe Tur; Tel Aviv University, Israel Prof. Anbo Wang; Virginia Polytechnic Institute and State University, USA Prof. David Webb; Aston University, UK Prof. Minghong Yang; Wuhan University of Technology, China Prof. Libo Yuan; Harbin Engineering University, China

International Honorary Committee Dr. Thomas Bosselmann; Siemens AG, Germany Dr. Richard Claus; NanoSonic Inc., USA Prof. Brian Culshaw; University of Strathclyde, UK Prof. John Philip Dakin; University of Southampton, UK Dr. Anthony Dandridge; Naval Research Laboratory, USA Dr.Gordon W. Day.; IEEE - The Institute of Electrical and Electronics Engineers, USA Dr. Thomas Giallorenzi; US Naval Research Laboratory and Optical Society of America, USA Prof. Masimitrsu Haruna; Osaka University, Japan

Prof. Kazuo Hotate; The University of Tokyo, Japan Prof. David Jackson; University of Kent, UK Dr. Alan D. Kersey; CiDRA, USA Prof. Ralf Th. Kersten; neuroConn GmbH, Germany Prof. Byoung Yoon Kim; KAIST, Korea Dr. Herve Lefevre; iXBlue, France Prof. Yanbiao Liao; Tsinghua University, China Dr. Anna Mignani; CNR IFAC, Italy Dr.David D. Sampson; The University of Western, Australia Prof. Eric Udd; Columbia Gorge Research, USA Mr Marc Voet; FBGS Inernational, Belgium Dr. Ryozo Yamauchi; Fujikura Ltd., Japan

Local Organizing Committee Dr. Jesús Mirapeix; University of Cantabria, Spain Dr. Adolfo Cobo; University of Cantabria, Spain Dr. Olga M. Conde; University of Cantabria, Spain Dr. Mauro Lomer; University of Cantabria, Spain Dr. Francisco Madruga; University of Cantabria, Spain Dr. Maria Ángeles Quintela; University of Cantabria, Spain Dr. Antonio Quintela; University of Cantabria, Spain Dr. Luis Rodríguez-Cobo; University of Cantabria, Spain Mr. José J. Valdiande; University of Cantabria, Spain Mr. Pedro Anuarbe; University of Cantabria, Spain Ms María Ruiz; University of Cantabria, Spain Mr. Rubén Ruiz; University of Cantabria, Spain Mr. Hany Shokry Girgis; University of Cantabria, Spain Mr. Rafael Hidalgo-Gato; University of Cantabria, Spain Mr. Eusebio Real; University of Cantabria, Spain Mr. Ismail Laarossi; University of Cantabria, Spain Mr. Asier García; University of Cantabria, Spain

Invited Speakers

Plenary Speakers

Special Session I: Tribute to Alan Rogers

The pioneer, the gentleman professor with deep knowledge, empathy and humanity Alan Kersey, Cidra Corp. (United States)

The complete gentleman in every respect with wit intelligence and humour: the fine

fellow indeed Robert A. Lieberman, Optical Security Sensing, (United States)

The active professor, the contributor for over 30 years, and the proposer for electrical

power measurement and distributed sensing Kazuo Hotate, The University of Tokyo (Japan)

The fine friend who welcomed your interests with immense warmth and intellectual support Petar Basic.

The fine intellect, stimulator of new ideas and imaginative engineer, the stimulating teacher, and the fine friend Vince Henderek

The family view Dan Rogers (Alan’s son)

NanoPhotonics: pushing sensing to its limits in size and speed

Prof. Dr. Niek van Hulst

ICFO – the Institute of Photonic Sciences and ICREA – Institució Catalana de Recerca i Estudis Avançats, Spain

Novel light-based technologies for biomedical application

Prof. Dr. Seok-Hyun Yun

Harvard Medical School-Wellman Center for Photomedicine Harvard-MIT Health Sciences and Technology, USA

Quantum technologies for sensing, metrology and imaging

Prof. Dr. Jonathan P. Dowling

Louisiana State University, USA

Special Session II: Three Decades of OFS Series

OFS: Thirty years of achievements science and technology Julian Jones, Heriot-Watt Univ. (United Kingdom)

Three decades of OFS commercialization: the dawn, present and future Alexis Mendez, MZH Engineering, PLC (United States)

Special Session III: New Photonic Sensing Concepts for a Healthier and More Secure World

Development and application of fiber Raman-probes for biomedical diagnosis and

environmental monitoring Jürgen Popp, Institute of Photonic Technology Jena (Germany)

Nanoscale sensing using optical fibres: new photonic architectures and surface

functionality enabling novel sensors Tanya Monro, The Univ. of Adelaide (Australia)

Towards 1’000’000 resolved points in a distributed optical fiber sensor Marcelo A. Soto, Ecole Polytechnique Fédérale Lausanne (Switzerland)

Optical sensors in the modernization of the electric power grid: digital substation

challenges Jim Blake, Alstom Grid Inc. (United States)

Optical fiber sensing in the oil and gas industry: overcoming challenges Chris Baldwin, Weatherford, Washington (United States) Regular Sessions

Plasmonic hot spots: theoretical and practical limit for sensor applications Byoungho Lee, Seoul National Univ. (Korea, Republic of)

Optical fibre sensing in metals by embedment in 3D printed metallic structures Robert R. Maier, Heriot-Watt Univ. (United Kingdom)

Direct laser writing in fiber: cladding photonics, optofluidic sensing, and smart catheters Peter R. Herman, Univ. of Toronto (Canada)

Wide and fast wavelength-swept fiber lasers based on dispersion tuning for real-time

OCT Shinji Yamashita, The Univ. of Tokyo (Japan)

The intelligent distributed acoustic sensing Tom Parker, Silixa, Ltd. (United Kingdom)

Distributed strain and temperature sensing based on Brillouin scattering in plastic

optical fibers Yosuke Mizuno, Tokyo Institute of Technology (Japan)

Hybrid fibers: a base for creating new sensing fibers Markus A. Schmidt, Friedrich-Schiller-Univ. Jena (Germany)

Precise sensing utilizing optical fiber for space craft Tadahito Mizutani, Japan Aerospace Exploration Agency (Japan)

Fiber optic system for the real time detection, localization, and classification of

damage in composite aircraft structures Edgar A. Mendoza, Redondo Optics, Inc. (United States)

Next generation of optical fibre sensors: new concepts and perspectives Luc Thévenaz, Ecole Polytechnique Fédérale de Lausanne (Switzerland)

TECHNICAL PROGRAM DEVELOPMENT

Monday 2 June

Special Session I: Tribute to Alan Rogers Monday 2 June 2014 2:00 PM - 2:35 PM 14:00: OFS23 Chair: J. M. López-Higuera, Univ. of Cantabria (Spain) 14:02: Session Chair: Brian Culshaw, Univ. of Strathclyde (United Kingdom)

14:06: The pioneer, the gentleman professor with deep knowledge, empathy and

humanity (Invited), Alan Kersey, Cidra Corp. (United States).

14:10: The complete gentleman in every respect with wit intelligence and humour: the

fine fellow indeed (Invited), Robert A. Lieberman, Optical Security Sensing, (United States).

14:14: The active professor, the contributor for over 30 years, and the proposer for

electrical power measurement and distributed sensing (Invited), Kazuo Hotate, The University of Tokyo (Japan).

14:18: The fine friend who welcomed your interests with immense warmth and

intellectual support (Invited), Petar Basic.

14:22: The fine intellect, stimulator of new ideas and imaginative engineer, the

stimulating teacher, and the fine friend (Invited), Vince Henderek. 14:26: Alan’s son, Dan Rogers.

Special Session II: Three Decades of OFS Series

Monday 2 June 2014 2:40 PM - 3:30 PM Session Chair: J.M. López-Higuera, Univ. de Cantabria (Spain)

14:40: OFS: Thirty years of achievements science and technology (Invited), Julian Jones, Heriot-Watt Univ. (United Kingdom)

The subject of optical fibre sensors was stimulated by a combination of key strategic applications and new enabling technologies. The dominant early drivers of OFS research were the hydrophone and the gyroscope, whilst the enabling technologies emerged from the field of optical communications: optical fibres, and semiconductor laser diodes. These foundations of the subject are clearly visible in the topics of the first OFS conference, now more than thirty years ago. Since then, the subject has broadened and matured: the range and nature of available optical fibre properties and components has embraced in-fibre gratings and micro-structured and photonic crystal fibres amongst many other innovations; and the scope of applications has extended well beyond the originally dominant sectors of defence and aerospace, to embrace almost all fields of human endeavour, from civil infrastructure to medicine. The OFS conference series provides a unique and coherent account of the origins of the field, the key milestones and actors in its development, and the clearest signposts to its progress. The lecture will put into perspective the development of our subject, its status in the wider world, and its directions for the future.

15:05: Three decades of OFS commercialization: the dawn, present and future (Invited), Alexis Mendez, MZH Engineering, PLC (United States)

Over the past three decades, fiber optic sensors (FOS) have made a complete transition from basic lab prototypes to successful commercial products. A broad variety of commercial sensors and instruments are nowadays readily available, which enjoy increased acceptance and widespread use in different fields and industries. FOS solutions are commonly used in real-life applications ranging from structural sensing and health monitoring of materials and structures; to downhole pressure and temperature sensors for oil and gas reservoir monitoring; to high voltage and high current sensing systems for the power industry; to biomedical patient devices—among others. The commercialization road has been slow-moving and rocky at times, but always progressive and dotted with multiple successful companies and products. This talk will provide a historical overview of FOS technology evolution and its associated commercialization efforts over the past 30 years. A historical summary will be made of the early FOS players and products, key present success stories and milestones, and envisioned future prospects. The main goal is to contrast the historical past trajectory against the maturity of its present market and future commercial outlook. Coffee Break 3:30 PM - 4:00 PM

Special Session III: New Photonic Sensing Concepts for a Healthier and More Secure World Monday 2 June 2014 4:00 PM - 6:30 PM Session Chairs: Manuel López-Amo, Univ. Pública de Navarra (Spain) José Luis Santos INESC Porto (Potugal)

16:00: Development and application of fiber Raman-probes for biomedical diagnosis and

environmental monitoring (Invited), Jürgen Popp, Institute of Photonic Technology Jena (Germany)

Here we describe our latest results on fiber optic probes for Raman spectroscopy, especially for medical applications and environmental sensing. By doing so novel Raman fiber probes for an intraoperative monitoring of the artheriosclerotic plaque in living rabbits will be presented. Furthermore, several Raman fiber concepts for an on-site monitoring of biogenic gases will be introduced.

16:30: Nanoscale sensing using optical fibres: new photonic architectures and surface

functionality enabling novel sensors (Invited), Tanya Monro, The Univ. of Adelaide (Australia)

Optical glasses and fibres can be imbued with the properties of nanomaterials, and fibres can be structured with features spanning from 0.02–20 microns. Adding in surface chemistries that offer molecular recognition, one can create sensors to detect specific small molecules or proteins. Emerging sensing architectures will be presented including dip sensors that operate on volumes comparable to a single cell, the detection of single nanocrystals from a distance and fibre-tip sensors.

17:00: Towards 1’000’000 resolved points in a distributed optical fiber sensor (Invited), Marcelo A. Soto, Ecole Polytechnique Fédérale Lausanne (Switzerland)

Increasing the number of resolved points, by either improving the spatial resolution or extending the measurement range, is one of the main challenges being currently faced in distributed optical fiber sensing. This paper explores the main parameters affecting the performance of Brillouin distributed fiber sensors and analyzes potential configurations and directions to reach one million equivalent resolved points.

17:30: Optical sensors in the modernization of the electric power grid: digital substation

challenges (Invited), Jim Blake, Alstom Grid Inc. (United States)

Optical sensors are advancing the modernization of the power grid, because of the reduced costs, environmental savings, safety, reliability, and metrology performance improvement. Optical current sensors with very wide digital dynamic range (from 1 mA to more than 150 kA) able to measures both AC and DC, and meets 0.1% accuracy requirements over a temperature range from -40 C to +60 C for the digital substation are required. Several leading edge applications of the optical current sensor will be presented, along with a discussion of the developing power system architectures that fully capture the advantages of this new technology. Challenges to face will be clearly identified.

18:00: Optical fiber sensing in the oil and gas industry: overcoming challenges (Invited), Chris Baldwin, Weatherford, Washington (United States)

Optical fiber sensors have evolved to withstand many operational challenges - including high temperatures, extreme pressures, and excessive hydrogen levels - in harsh environments. Advances in fiber design and sensing techniques have helped to build rugged and reliable sensing architectures. This paper provides an overview of improvements and technical achievements over the past two decades.

Tuesday 3 June

Opening Remarks Tuesday 3 June 2014 9:00 AM - 9:30 AM Mr. Ignacio Diego Palacios, President of the Cantabria Government Prof. José Carlos Gomez Sal, Rector of the University of Cantabria Prof. José Miguel López-Higuera, University of Cantabria, Spain, OFS23 General Chair and Prof. Julian Jones, Heriot Watt University, UK, OFS23 Chair Plenary Presentation Tuesday 3 June 2014 9:30 AM - 10:30 AM Chair: Julian Jones, Heriot Watt University, UK

NanoPhotonics: pushing sensing to its limits in size and speed (invited), Niek F. van Hults. ICFO-The Institute of Photonic Sciences and ICREA-Institució Catalana de Recerca i Estudis Avançats (Spain)

Optical fibres are historically at the base of near-field optics for nanoscale sensing and microscopy, opening routes to the detection of single molecules, quantum dots, protein complexes, etc. Fibres with conventional sub-wavelength aperture however are inefficient; while fixtures with plasmonic nano-antenna probes are highly superior for light control on the nanoscale. In this presentation I will focus on optical control, both in space and time, by resonant nanoantennas and phase shaped fs pulses. For spatial control, we manipulate single photon emitters close to optical antennas (monopole dipole, multipole and multi element) to explore nanoscale field concentration, directionality, spectral resonances and sensing applications. Exploiting resonant antenna designs the emission can be enhanced up to 1000 times and steered into narrow forward angular cones. For temporal control, we exploit phase shaped fs pulses to drive resonant antennas and single quantum systems to dynamically control both their fs response and nanoscale fields. Both amplitude and optical phase of antennas is directly captured. Interestingly when applied to single-molecules and even molecular antenna complexes a superior degree of coherent control beyond the ensemble is realized. In conclusion, with this presentation I hope to provide insight on the advances and potential of modern photonics at the cross-roads between nm and fs scales

This work is supported by ERC-Advanced Grant 247330 on NanoAntennas, MICIINN Consolider CSD2007-046,

Fundació CELLEX Barcelona and LASERLAB-EUROPE.

Coffee Break 10:30 AM - 11:00 AM

Session 1: Physical, Mechanical, Electromagnetic, Interferometric and Polarimetric Sensors including Gyroscopes I Tuesday 3 June 2014 11:00 AM - 12:30 PM Session Chairs: Alan D. Kersey, CiDRA (United States) Li-Bo Yuan, Harbin Engineering Univ. (China) Time: 11:00 - 11:30; Invited Paper 9157-673

Plasmonic hot spots: theoretical and practical limit for sensor applications Byoungho Lee, Seoul National Univ. (Korea, Republic of) . Surface plasmon resonance (SPR) has been actively researched for sensor applications. Based on the subwavelength scale enhancement of light field and its sensitivity to refractive index, SPR can be used for surface enhanced Raman spectroscopy and various bio and chemical sensors. This talk will provide comparative overview of the potentials of SPR for fiber sensors and its practical limitations in implementation. Time: 11:30 - 11:45; Paper 9157-192

Ferrule-top nano-mechanical resonator with multilayer graphene film Jun Ma, Wei Jin, Hoi Lut Ho, Chao Wang, The Hong Kong Polytechnic Univ. (Hong Kong, China)

Compact ferrule-top nano-mechanical resonators with all-fiber optical interrogation are demonstrated. The resonators comprise of a suspended multi-layer graphene film supported by a ceramic ferrule with a bore diameter of 125 μm. The mechanical resonance of the graphene film is excited and detected via a single optical fiber cable, and experimental test shows that the resonant frequency and quality factor of the resonators are in the range of 170-520 kHz and 58.4-250, respectively. The integration of graphene resonator with optical fiber transmission and interrogation would allow the development of practical fiber-optic sensors for force, mass and pressure measurements. Time: 11:45 - 12:00; Paper 9157-195 Electric field sensing with high spatial resolution via a charged "flying particle" optically guided inside hollow-core PCF Dmitry S. Bykov, Oliver A. Schmidt, Tijmen G. Euser, Max Planck Institute for the Science of Light (Germany); Philip S. Russell, Max Planck Institute for the Science of Light (Germany), Univ. of Erlangen-Nuremberg (Germany)

We report an electric field sensor based on a charged microparticle that is optically trapped, and moved to and fro, inside a hollow-core photonic crystal fibre (PCF). Transverse electric fields displace the particle, altering the transmitted optical power. The transmission change is found to be linear with fields in the 0.1-50 kV/m range, with a flat frequency response from 0.01 to ~1 kHz. In a first test, the field pattern near a multi-element electrode was resolved with a spatial resolution of 1 mm. This unique "flying particle" sensor allows electric field mapping over long distances (the lowest loss hollow core PCF has a 3 dB length of ~3 km) and is suitable for inaccessible or harsh environments.

Time: 12:00 - 12:15; Paper 9157-205

Temperature compensation of fiber-optic current sensors

Georg M. Müller, Lin Yang, Berkan Gülenaltin, Andreas Frank, Klaus Bohnert, ABB Ltd. (Switzerland)

We theoretically and experimentally demonstrate inherent temperature compensation of an interferometric reflective fiber-optic current sensor. An appropriately tuned fiber retarder balances various contributions to the temperature dependence of the signal. The technique is extended from fiber coils with negligible linear birefringence to coils made of low-birefringent sensing fiber but with non-negligible bend-induced birefringence as well as to coils of spun highly-birefringent sensing fiber with influences from their elliptical birefringence and its temperature dependence. Some parameter sets of particular interest are considered. Insensitivity to temperature is demonstrated to within <±0.2% over outdoor temperature ranges.

Time: 12:15 - 12:30; Paper 9157-577

Sensitive strain measurements with a fiber Bragg-grating ring resonator Pietro Malara, CNR, Istituto Nazionale di Ottica (Italy); C. E. Campanella, Politecnico di Bari (Italy); Antonio Giorgini, Saverio Avino, R. Zullo, G. Gagliardi, Paolo De Natale, CNR, Istituto Nazionale di Ottica (Italy)

We describe a novel strain sensor based on a fiber Bragg grating (FBG) ring resonator. The spectrum of this resonator consists of equally-spaced resonances, exhibiting a frequency splitting proportional to the reflectivity of the intracavity FBG. A strain applied to the FBG causes a shift of the bragg wavelength, and thus a variation of the resonance splitting. The splitting is insensitive to the

thermal/strain noise affecting the fiber in the region outside the FBG. The sensitivity and resolution of the sensor are analyzed in detail, showing that a subpicostrain resolution can be easily achieved with an optimized setup.

Lunch Break 12:30 PM - 2:00 PM

Session 2: Physical, Mechanical, Electromagnetic, Interferometric and Polarimetric Sensors including Gyroscopes II Tuesday 3 June 2014 2:00 PM - 3:30 PM Session Chairs: Moshe Tur, Tel Aviv Univ. (Israel); David J. Webb, Aston Univ. (United Kingdom)

Time: 14:00 - 14:30; Invited Paper 9157-674

Optical fibre sensing in metals by embedment in 3D printed metallic structures Robert R. Maier, Heriot-Watt Univ. (United Kingdom) . Additive manufacturing or 3D printing of structural components in metals is potentially revolutionising the manufacturing industry. Embedded sensing in such structures opens a route towards SMART metals, providing added functionality, intelligence and enhanced performance in many components. Such embedded sensors would be capable of operating at extremely high temperatures by utilising regenerated fibre Bragg gratings and in fibre Fabry-Perot cavities. Time: 14:30 - 14:45; Paper 9157-558

Tapered polarization-maintaining fiber sensor based on analysis of polarization evolution Ping Lu,Jia Song, Graeme Niedermayer, Jeremie Harris, Liang Chen, and Xiaoyi Bao, Univ. of Ottawa (Canada)

We proposed and experimentally demonstrated a novel tapered polarization-maintaining fiber (PMF) sensor based on analysis of polarization evolution. The unique structure of the tapered PMF demonstrates extraordinary polarization characteristics under external disturbance such as twists and magnetic fields, exhibiting great advantages of compactness, high sensitivity, and versatility. Time: 14:45 - 15:00; Paper 9157-569

Wind tunnel unsteady pressure measurements using a differential optical fiber Fabry-Perot pressure sensor Ricardo N. Correia, Stephen E. Staines, Stephen W. James, Nicholas Lawson, Kevin P. Garry, Ralph P. Tatam, Cranfield Univ. (United Kingdom)

A differential extrinsic optical fiber Fabry-Perot based pressure sensor has been developed and benchmarked against a conventional piezoresistive Kulite pressure sensor. The sensors were placed on the fuselage of a 1:10/3 sub-scale model of a Scottish aviation Bulldog, which was placed in a wind-tunnel. Pressure tappings that surrounded the sensors aided the mapping of pressure distribution around this section of the fuselage. The results obtained from the fibre optic pressure sensor are in good agreement with those obtained from the Kulite and from the pressure tappings.

Time: 15:00 - 15:15; Paper 9157-493

Multipoint two-dimensional curvature optical fibre sensor David Barrera-Villar, Salvador Sales, Univ. Politècnica de València (Spain)

Multicore optical fibre can be used to implement multidimensional optical fibre sensors. In this paper, an array of four multiplexed FBGs is inscribed in a multicore optical fibre in order to obtain a multipoint curvature sensor. An improved FBG inscription technique is used in order to mitigate the several issues that arise during the inscription of FBGs in this kind of optical fibres. The optical fibre sensor is described and theoretically analysed in order to obtain the magnitude and direction of the curvature and also the strain produced by external forces. Time: 15:15 - 15:30; Paper 9157-153

Performance of resonator fiber optic gyroscope using external-cavity laser stabilization and optical filtering Tiequn Qiu, Jianfeng Wu, Lee K. Strandjord, Glen A. Sanders, Honeywell Technology (United States)

A bench-top resonator fiber optic gyroscope (RFOG) was assembled and tested, showing encouraging progress toward navigation grade performance. The gyro employed a fiber length of 19 meters of polarizing fiber for the sensing coil which was wound on an 11.5 cm diameter PZT cylinder. A bias stability of approximately 0.1 deg/hr was observed over a 2 hour timeframe, which is the best

bias stability reported to date in an RFOG to our knowledge. Special care was taken to minimize laser phase noise, including stabilization to an optical cavity which was also used for optical filtering, giving angle random walk (ARW) values in the range of 0.008 deg/rt-hr. The ARW performance and bias stability are within 2x and 10x, respectively, of many civil inertial navigation grade requirements.

Coffee Break 3:30 PM - 4:00 PM

Session 3: Physical, Mechanical, Electromagnetic, Interferometric and Polarimetric Sensors including Gyroscopes III Tuesday 3 June 2014 4:00 PM - 5:00 PM

Session Chairs: Reinhardt Willsch, Institut für Photonische Technologien e.V. (Germany); Michel J. Digonnet, Stanford Univ. (United States) Time: 16:00 - 16:30; Invited Paper 9157-675

Direct laser writing in fiber: cladding photonics, optofluidic sensing, and smart

catheters Peter R. Herman, Univ. of Toronto (Canada) ¡ The manipulation of femtosecond laser light inside transparent media can be directed on varying interaction pathways to open new directions for creating dense memory storage, three-dimensional (3D) optical circuits, 3D microfluidic networks and high-speed scribing tracks. The presentation follows these fundamental interactions towards controlling glass processes in optical fibers that enable highly functional and compact devices to form with the benefits of seamless integration with single mode optical fibers. 3D optical circuits are formed within the fiber cladding that couple efficiently with the fiber core waveguide while chemical etching of laser-generated nanogratings is further applied to open microfluidic channels and optical resonator components for building into 3D opto-fluidic microsystems. Such all-fiber microsystems offer reduced fabrication and packaging costs for enabling more compact and integrated approaches in telecommunication, fiber laser, sensing, lab-in-fiber, smart medical catheter and biomedical probing devices. Time: 16:30 - 16:45; Paper 9157-410

In-line high-speed all-fiber polarimeter with true real-time acquisition for sensor systems based on fast polarization rotation Vitaly Mikhailov, Bryan Rabin, Paul S. Westbrook, OFS Labs. (United States)

We report on an all fiber polarimetric optical detector system suitable for sensor applications that rely on fast polarization measurements. Our device exhibits an RF bandwidth of 500 MHz and an optical calibration bandwidth of over 30nm in the S-C-L-bands (1460-1625 nm) and above, with minimal PMD, PDL, and return loss when used in-line. A set of automated self-calibration procedures ensure high accuracy without the need for external polarization optics or reference polarimeters. We integrated our polarimeter into an acquisition systems capable of measuring fast polarization rotation events over long period of time with 250 MS/s peak sampling rate.

Time: 16:45 - 17:00; Paper 9157-616

Low noise and low drift in a laser-driven fiber optic gyroscope with a 1-km coil Jacob N. Chamoun, Anna Evans, Stanford Univ. (United States); Frédéric A. Mosca, IXBLUE (France); Michel J. F. Digonnet, Stanford Univ. (United States)

We report an experimental fiber optic gyroscope (FOG) utilizing a 1085-m coil of 8-cm diameter driven with a laser of 10-MHz linewidth, with a record rotation-rate noise as low as 0.2 deg/h/√Hz and a drift below 0.038 deg/h. Simulations and comparison to the measured performance of a similar 150-m FOG show that the noise is limited approximately equally by coherent backscattering and polarization coupling in the sensing coil, and unaffected by the Kerr effect.

Poster Session I (112 papers)

Tuesday 3 June 2014 5:00 PM - 6:30 PM Panel or Board number 1/ Paper 9157-15

Species discrimination in plasma welding spectra by means of Principal and Independent Component Analysis Eusebio Real, Jesus Mirapeix, Olga M. Conde, Ruben Ruiz-Lombera, Luis Rodriguez-Cobo, Jose-Miguel Lopez-Higuera, Univ. de Cantabria (Spain)

Principal and Independent Component Analysis are used in this paper to provide a discriminationong those species participating in the plasma of welding spectra. This approach might be useful for spectral line identification for emission spectroscopy, especially for online welding diagnostics and laser induced breakdown spectroscopy. In this case, the feasibility of this proposal will be analyzed by means of arc-welding experiments where different plasma species will be separated by the proposed processing scheme. P2/Paper 9157-40

Cavity ring-down with OTDR for remote sensing Daniel Passos, Susana Silva, Manuel B. Marques, Orlando Frazão, INESC Porto (Portugal)

This work presents a demonstration of the potential of fiber cavity ring-down for remote sensing, by using an OTDR to send impulses down ~20 km of optical fiber at the end of which the fiber ring cavity was placed. P3/Paper 9157-450

Performance analysis of the sweep-free Brillouin optical time-domain analyzer (SF-BOTDA) Asher Voskoboinik, Alan E. Willner, Univ. of Southern California (United States); Moshe Tur, Tel Aviv Univ. (Israel)

Using simultaneous multiple pumps and probes to estimate the Brillouin Frequency Shift along an optical fiber, as in the Sweep-free BOTDA (SF-BOTDA) technique, saves measurement time but involves quite a few tradeoffs. Through simulations this work studies the role of the number of tones, their granularity and the desired spatial resolution and dynamic range on the obtained BFS accuracy for different signal to noise ratios and number of averages. P4/Paper 9157-46

Fibre optical sensor for simultaneous measurement of pressure, temperature and refractive index Ralf D. Pechstedt, Oxsensis Ltd. (United Kingdom)

A fibre optical sensor for the simultaneous measurement of pressure, temperature and refractive index has been demonstrated. The sensor is based on a multi-cavity design and employs a monolithic sapphire transducer element. P5/Paper 9157-51

Novel FBG sensors based on cladding surface microstructures Yu-Tang Dai, Minghong Yang, Joseph M. Karanja, Qiancheng Zhao, Wuhan Univ. of Technology (China)

Novel FBG sensors based on cladding microstructures are proposed, which include micro-holes array, single or double spiral and straight groove types. Through depositing different sensitive film, the microstructured FBG sensors can be applied to fiber optic magnetic field sensor, hydrogen sensor and humidity sensor. As a developing example, a spiral type microstructured FBG magnetic field sensor is demonstrated. The testing results show that, the sensitivity of the spiral types probe can be promoted 4-6 times more than that of the non-microstructured standard FBG probe. The double spiral probe is better than the single spiral type.

P6/Paper 9157-70

Eliminating the influence of polarization instability using time-wavelet energy spectrum for FBG-FP static-strain sensing Wenzhu Huang, Wentao Zhang, Tengkun Zhen, Institute of Semiconductors (China); Fusheng Zhang, Shijiazhuang Tiedao Univ. (China); Fang Li, Institute of Semiconductors (China)

The fluctuation of polarization may cause wrong demodulation results in high-resolution static-strain sensing based on FBG-FP. This paper presents a polarization-insensitive demodulation algorithm using time-wavelet energy spectrum for single mode fiber (SMF) based FBG-FP sensor. This method can eliminate the influence of polarization instability effectively. Time-wavelet energy spectrum is calculated to get the energy distribution of the reflectance spectrums of FBG-FP on the timeline. The maximum value of the energy distribution is used to obtain the strain signal. In the laboratory, a high-resolution strain demodulation result without polarization controller is obtained. P7/Paper 9157-71 π-phase-shifted FBG for improving static-strain measurement resolution based on triangle-wave laser tuning technique

Wenzhu Huang, Wentao Zhang, Institute of Semiconductors (China); Tengkun Zhen, Shijiazhuang Tiedao Univ. (China); Ce Bian, Institute of Semiconductors (China); Yanliang Du, Shijiazhuang Tiedao Univ. (China); Fang Li, Institute of Semiconductors (China)

In this paper, π-phase-shifted FBG (π-FBG) is used for high-resolution static-strain sensing. A novel laser tuning technique based on triangle-wave voltage driver is proposed to improve wavelength scanning stability of tunable laser. And a static-strain demodulation algorithm based Gauss curve fitting and peak detection is tested. As the reflectance spectrum of π-FBG have high signal-to-noise ratio, a static-strain resolution of 0.83 nε is obtained in a vacuum environment, which shows that the proposed system have a good application prospect for geophysics applications.

P8/Paper 9157-73 Distributed feedback fiber laser acoustic emission sensor for concrete structure health monitoring Gengjie Hao, Wentao Zhang, Wenzhu Huang, Institute of Semiconductors (China); Baochen Sun, Shijiazhuang Tiedao Univ. (China); Fang Li, Institute of Semiconductors (China)

This paper introduces a highly-sensitive fiber optical acoustic emission (AE) sensor and a parameter analysis method aiming at concrete structure health monitoring. Distributed feedback fiber-laser (DFB-FL), which is encapsulated to have a high acoustic sensitivity, is used for sensor unit of the AE sensor. The AE signal of concrete beam in different work stages, based on the four-point bending experiment of the concrete beam, is picked up, and the relationship between the concrete beam work stages and the AE parameter is found. The results indicate that DFB-FLAES can be used as sensitive transducers for recording acoustic events and forecasting the imminent failure of the concrete beam. P9/Paper 9157-87

Orientation-recognized rotation measurement using single polarimetric multi-mode tilted fiber grating Fu Liu, Tuan Guo, Libin Shang, Zhaochuan Zhang, Fa Du, Bai-Ou Guan, Jacques Albert, Jinan Univ. (China)

The polarimetric sensing characteristics of multi-mode-fiber based tilted fiber Bragg grating (MMF-TFBG) have been analyzed and experimentally demonstrated. The physical “enlarged” fiber core enables the tilted gratings to excite multi high-order core modes with significantly different polarization dependence and well-defined “comb” profiles which are spectrally separated at different wavelength. Orientation-recognized twist/rotation measurement (-90o to 90o) has been achieved with sensitivity of 0.075 dB/deg by using a cost-effective double-path power detection (power monitoring of two orthogonal-polarimetric odd core-modes, i.e. LP11 and LP12).

P10/Paper 9157-90

Polarization optical fiber sensor for distributed current monitoring Luca Palmieri, Univ. degli Studi di Padova (Italy); Davide Sarchi, Prysmian S.p.A. (Italy); Andrea Galtarossa, Univ. degli Studi di Padova (Italy)

A new technique to distributedly monitor intense current along high energy electric cables is presented and experimentally validated. The new technique is based on the distributed polarization measurement of Rayleigh backscattered light and on Faraday rotation of polarization induced by the electric current flowing in the cable. While current monitoring by Faraday rotation in optical fibers isong the first examples of optical fiber sensors, this is the first time, to best of our knowledge, that a distributed current sensor is implemented. Preliminary experimental tests have been performed on a 40-m-long electric cable, with currents varying from 0 to 2.5 kA, using standard telecommunication fibers non-optimized to the specific aim. Results confirm the viability of the approach.

P11/Paper 9157-101

Highly integrated FP/FBG sensor for simultaneous measurement of strain and temperature under high temperature

Qin Liu, Xi'an Institute of Optics and Precision Mechanics (China); Zeng-Ling Ran, Yunjiang Rao, Shu-Cheng Luo, Hui-Qin Yang, Ya Huang, Univ. of Electronic Science and Technology of China (China)

An inline fiber-optic micro Fabry–Perot (MFP) cavity and a short fiber Bragg grating (SFBG) is overlapped to form a highly integrated MFP/SFBG sensor for simultaneous measurement of temperature and strain under high temperature (300°C). The F-P cavity is fabricated on an all-silica fiber by using the 157nm laser micro-machining technique while the SFBG is written on a GeO2 doped high temperature photon sensitive fiber at the same position of the MFP cavity. As the MFP cavity and the SFBG have different sensitivity coefficients to temperature and strain, they can be utilized for realization of dual parameters measurement. Experimental results show that simultaneous measurement of strain and temperature is achieved under high temperature up to 300°C. P12/Paper 9157-130

Highly sensitive current sensor based on an optical microfiber loop resonator incorporating low index polymer Min-Seok Yoon, Young-Geun Han, Hanyang Univ. (Korea, Republic of)

A highly sensitive current sensor based on an optical microfiber loop resonator (MLR) incorporating low index polymer is proposed and experimentally demonstrated. The microfiber with a waist diameter of 1 um is wrapped around the nicrhrome wire with low index polymer coating and the optical MLR is realized. The use of the microfiber and low index polymer with high thermal property

can effectively improve the current sensitivity of the proposed MLR-based sensing probe to be 437.9 pm/A^2, which is ~10 times higher than the previous result.

P13 / Paper 9157-146

Temperature and pressure transducer based on FBG for large diameter water pipes Antonio Quintela

1; María J. Pallol

2; Hany S. Roufael

1; Oscar Martinez

2, Jose D. San-Emeterio

2; José Miguel López-

Higuera1,

1Univ. de Cantabria (Spain);

2COPSESA S.A. (Spain)

A specific temperature and pressure optical fiber transducer is presented in this paper. By using a customized fiber reinforced plastic membrane with embedded Fiber Bragg Gratings, the fluid pressure and temperatures changes are converted in optical wavelength displacements. The membrane and the transducer custom design allows a suitable measurand discrimination. The transducer is implemented, characterized and calibrated. Its feasibility to be used on large diameter water pipes has been successfully validated by means of field trials. Many of these transducers will be optically multiplexed to monitoring these infrastructures.

P14/Paper 9157-149

Effect of a waist diameter of a polarization-maintaining fiber onbient index sensitivity Min-Seok Yoon, Soo Kyung Kim, Cheol-Ju Kang, Young-Geun Han, Hanyang Univ. (Korea, Republic of)

We investigate the effect of a waist diameter of a polarization-maintaining fiber (PMF) onbient index and temperature sensitivities by configuring a Sagnac loop interferometer. To make the PMF sensitive to external index change, a micro-tapering technique is exploited to fabricate the tapered PMF. The Sagnac loop interfoermeter is fabricated by using the tapered PMF with various waist diameters. The reduction of the PMF diameter results in the enhancement of thebient index sensitivity of the tapered-PMF-based Sagnac interferometer. However, the temperature sensitivities of the proposed Sagnac interferometers are not changed by reducing the waist diameters of the PMFs. P15/Paper 9157-150

Hybrid Sagnac interferometer with high measurement resolution for smultaneous measurement ofbient index and temperature Oh-Jang Kwon, Young-Geun Han, Hanyang Univ. (Korea, Republic of)

A simple technique for simultaneous measurement of the concentration of ethylene glycol and temperature by using a hybrid Sagnac interferometer is proposed and experimentally demonstrated. The hybrid Sagnac interferometer is configured by inserting a long-period fiber grating (LPFG) and a D-shaped polarization-maintaining fiber (PMF) into a Sagnac interferometer. By partially removing the cladding of the PMF, we make the Sagnac interferometer sensitive tobient index by exposing the core region of the D-shaped PMF to external circumstance. The determinant of the sensitivity matrix of the proposed sensing probe is improved by using the negative temperature sensitivity of the LPFG.

P16/Paper 9157-161

Simultaneous measurement of temperature and static strain using FBG Fabry-Perot interferometer in polarization maintaining fiber Ryotaro Uchimura, Atsushi Wada, Shingo Tekuramori, Makoto Takeuchi, Osamu Tsukida, Satoshi Tanaka, Nobuaki Takahashi, National Defense Academy (Japan)

A Fiber Bragg Gratings (FBG) have been used as a sensor head for measurement of temperature and static strain. However, a standard FBG sensor, which is constructed on single-mode fiber, cannot simultaneously measure both temperature and static strain since the sensor has cross-sensitivity between them. The cross-sensitivity problem can be solved by using an FBG constructed on a polarization maintaining fiber (PM-FBG) instead of a standard FBG. In this paper, we report improvement on the sensing resolution for the simultaneous measurement of temperature and static strain. An Fabry-Perot interferometer constructed with PM-FBG (PM-FBG-FPI) is introduced as a sensor head. The fine structure of an PM-FBG-FPI reflection spectrum enables high resolution detection of wavelength shifts. The resulting high resolution measurement is demonstrated experimentally.

P17/Paper 9157-174

Performance improvements in fiber-bending pressure sensors by using depressed cladding erbium doped fiber

Joao B. Rosolem, Ariovaldo A. Leonardi, Danilo C. Dini, CPqD (Brazil)

In this work, we describe improvements in the performance of fiber-bending pressure sensors by using depressed cladding erbium doped fiber (DC-EDF). In this study, we compare the accuracy of DC-EDF sensor with bending sensor using standard single-mode fiber. Furthermore, we present a new technique to use this sensor in such way their response to pressure variation is dependent only with theplified spontaneous emission (ASE) peak wavelength in S-band. In other words, we demonstrate that they are insensitive to the signal and pumping power variations. P18/Paper 9157-207

Fiber optic dynamic electric field sensor based on nematic liquid crystal Fabry-Perot etalon Myeong Ock Ko, Sung-Jo Kim, Jong-Hyun Kim, Min Yong Jeon, Chungnam National Univ. (Korea, Republic of)

We propose a fiber-optic dynamic electric field sensor using a nematic liquid crystal (NLC) Fabry-Perot etalon and a wavelength-swept laser. The transmission wavelength of the NLC Fabry-Perot etalon depends on the applied electric field intensity. The change in the effective refractive index of the NLC is measured while changing the applied electric field intensity. It decreases from 1.67 to 1.51 as the applied the electric field intensity is increased. Additionally, we successfully measure the dynamic variation of the electric field using the high-speed wavelength-swept laser. By measuring the modulation frequency of the transmission peaks in the temporal domain, the frequency of the modulated electric field can be estimated.

P19/Paper 9157-210

Fibers and sensors for monitoring nuclear power plants operation Oleg V. Butov, Yurii K. Chamorovskii, Konstantin M. Golant, Institute of Radio Engineering and Electronics (Russian Federation); Igor A. Shevtsov, Artem N. Fedorov, Prolog LLC (Russian Federation)

The radiation resistant sensor system for measuring deformations of the fuel channels of the RBMK-1000 nuclear power reactor is by now developed and tested. Concept of the system is the application of metal-coated radiation resistant nitrogen-doped-silica-core fiber and Bragg gratings written in it. Performance of the fiber and sensor elements measured in conditions of the extreme radiation environment inside core of operating nuclear reactors is being reported.

P20/Paper 9157-213

Acoustic antenna based on fiber laser hydrophones François-Xavier Launay, Renaud Bouffaron, Raphael Lardat, Gérard Roux, Martine Doisy, Christian Bergogne, Thales Underwater Systems (France)

For underwater surveillance applications, an all-optical acoustic array technology allows enhanced capabilities compared to conventional piezoelectric antenna in terms of compactness, robustness and large distance remote interrogation through small diameter optical cable. One major issue about this kind of antenna is the design of a compact sensitive optical hydrophone which is optimized for reduced temperature sensitivity and high static pressure capability. This paper presents the results obtained on a first full optical antenna panel based on an innovative wideband fiber laser hydrophone. The presented mock-up includes 12 fiber laser optical hydrophones interrogated through a 12 km lead optical cable. P21/Paper 9157-217

Fiber taper combined with magnetic fluid for magnetic field Azam Layeghi, Hamid Latifi, Shahid Beheshti Univ. (Iran, Islamic Republic of); Orlando Frazao, INESC Porto (Portugal)

A magnetic field sensor using a non-adiabatic tapered optical fiber (NATOF) interacting with magnetic fluid (MF) nanoparticles is proposed and experimentally demonstrated. The NATOF is surrounded by a MF whose RI changes with external magnetic field which MF is as a cladding of tapered fiber. The Output interference spectrum is shifted by the change of the applied magnetic field intensity in the range up to 44 mT with a sensitivity of -7.17×10-2 nm/mT.

P22/Paper 9157-232

Multiparameter measurement using a double-Y-shaped suspended-core fiber in a fiber loop configuration Susana Silva, INESC Porto (Portugal); Hardy Baierl, CNRS, Univ. de Limoges (France); Jean-Louis Auguste, Raphael Janier, Phillipe Roy, CNRS, XLIM Institut de Recherche (France); José M. Baptista, INESC Porto (Portugal); José Santos, Orlando Frazão, INESC Porto (Portugal), Univ. do Porto (Portugal)

In this work, an all-fiber loop mirror using a four-bridge silica fiber with a double-Y-shaped suspended-core is presented for the measurement of strain and torsion.

P23/Paper 9157-273

Fiber optic magnetic field sensor based on magnetic fluid and etched Hi-Bi fiber loop mirror Jing Wang, Ciming Zhou, Dian Fan, Yiwen Ou, Wuhan Univ. of Technology (China)

A novel magnetic field sensor consisting of magnetic fluid (MF) and etched highly birefringent fiber loop mirror (Hi-Bi FLM) is proposed in the paper. The sensor is based on the etched FLM interferometer by using the property of the controllable refractive index of MF under external magnetic field. The refractive index of MF is changed by a tunable magnetic field and the resonant dip wavelength produced by the FLM shifts correspondingly. The magnetic field intensity can be measured by detecting wavelength shift. High sensitivity of 11.31pm/Oe and a resolution of 0.1Oe are obtained for the proposed magnetic field sensor.

P24/Paper 9157-281

Strain and temperature sensing characteristics of asymmetric-twin-core PCF-based hybrid Mach-Zehnder interferometer Khurram Naeem, Gwangju Institute of Science and Technology (Korea, Republic of); Bongkyun Kim, Beckman Laser Institute-Korea, Dankook Univ. (Korea, Republic of); Youngjoo Chung, Gwangju Institute of Science and Technology (Korea, Republic of)

We investigate the strain and temperature sensing characteristics of an inline hybrid Mach-Zehnder interferometer (HMZI) formed by splicing a short section of asymmetric twin-core photonic crystal fiber (ATC-PCF) between two single mode fibers. For fixed

polarization state of input light, two cores due to their asymmetric construction strongly support the propagation of few dominant core-modes, specifically, a lowest-order, and a set of lowest- and higher-order core-modes, respectively; this leads to a unique phase difference between inter-core and intra-core mode fiber interferometers in our ATC-PCF based HMZI. Experimental results reveal that,ong different orders of interferometers involved in the HMZI, the interferometer with higher-value of modal refractive index difference exhibit larger phase-shift sensitivity to the surrounding perturbations.

P25/Paper 9157-282

Comparison of FBG responses to static and dynamic pressures Ehud Shafir, Shlomi Zilberman, Avi Ravid, Benny Glam, Gabi Appelbaum, Alex Fedotov Gefen, Yair Saadi, Noam Shafir, Garry Berkovic, Soreq Nuclear Research Ctr. (Israel)

FBGs respond to external pressures in ways that reflect both the strain-optic effect and the geometrical variations, both induced by the applied pressure. While the response to static isotropic pressure is quite straight forward and intuitive, the response to anisotropic shock waves is much more complex and depends also on the relative orientation between the fiber and the shock propagation direction. We describe and explain experimental results for both cases.

P26/Paper 9157-296

Opto-magnetostrictive current measurement instrument for high voltage environments Fábio V. de Nazaré, Marcelo M. Werneck, Univ. Federal of Rio de Janeiro (Brazil)

The authors present the development of a opto-magnetostrictive current monitoring device intended to be used in situations where high voltages are involved. The system offers not only measurement reliability, but to be also practical and light weighted. Fiber Bragg gratings (FBG) are employed in the measurement procedure: the current is acquired using a hybrid sensor head set-up, that is, an FBG together with a magnetostrictive rod.

P27/Paper 9157-311

Refractive index sensitivity of long-period fiber gratings written in thinned cladding fiber by CO2 laser Yunhe Zhao, Yunqi Liu, Qiang Guo, Tingyun Wang, Shanghai Univ. (China)

We demonstrate the fabrication of the long-period fiber gratings (LPFGs) in the thinned cladding fiber (TCF) using CO2 laser. The sensing response of the gratings to surrounding refractive index has been investigated experimentally. The LPFGs written in the TCF could be used as the high sensitive refractive index sensors.

P28/Paper 9157-320 Self-referenced temperature sensor based on a polymer optical fiber macro-bend Alberto Tapetado Moraleda, Plinio Jesús Pinzón Castillo, Univ. Carlos III de Madrid (Spain); Joseba Zubia Zaballa, Univ. del País Vasco (Spain); Isabel Pérez Garcilópez, Carmen Vázquez García, Univ. Carlos III de Madrid (Spain)

The design and development of a plastic optical fiber (POF) macrobend temperature sensor is presented. The sensor has a linear response versus temperature at a fixed bend radius, with a sensitivity of 8.2∙(10)^(-4) (ºC)^(-1) and a 8% non-linearity full scale error. The sensor system uses the power variation between two discrete wavelengths for auto reference purposes. An analysis for selecting operation wavelengths has been carried out in order to optimize the response of the sensor. The proposed sensor can be used in harsh environment and has a low-cost.

P29/Paper 9157-322

A tactile sensing element based on a hetero-core optical fiber for force measurement and texture detection Hiroshi Yamazaki, Yuya Koyama, Kazuhiro Watanabe, Soka Univ. (Japan)

This report describes a new tactile sensing element based on a hetero-core optical fiber for force measurement and texture detection. Hetero-core optical fibers have high sensitivity of macro-bending at local portion and temperature independency, including advantages of optical fiber itself. The developed tactile sensing element could measure theount of force and detect minute structures of texture. In the report it is indicated that the sensing element has high accuracy against applied force and could detect 0.1-mm-height bump dots with spatial resolution of 0.8 mm. P30/Paper 9157-327

Interrogation of miniature extrinsic Fabry-Pérot sensor using path matched differential interferometer and phase generated carrier scheme Fuyin Wang, Jiehui Xie, Zhengliang Hu, Shuidong Xiong, Hong Luo, Yongming Hu, National Univ. of Defense Technology (China)

Study of fiber optic extrinsic Fabry-P\'{e}rot sensors utilizing state-of-the-art MEMS technology mostly focus on sensor fabrication for various applications, while the signal interrogation is still insatiable to current application. In this paper, we propose a white light path matched differential interferometer dynamic sensing system utilizing phase generated carrier demodulation scheme. A step motor with a movable mirror and a fiber-wound piezoelectric transducer string are used to act path matching and phase modulation

respectively. Experimental results show that the sensing signal could be correctly recovered with low distortion and the phase noise spectrum level is less than -100 dB re. rad/sqrt.Hz. above 2.5 kHz

P31/Paper 9157-329

Long-term stable sapphire fiber Bragg grating sensors at 1400°C Tobias Habisreuther, Tino Elsman, Zhiwen Pan, Albrecht Graf, Institut für Photonische Technologien e.V. (Germany); Petteri Ahonen, Katarina Grujic, Teknova AS (Norway); Sigurd Simonsen, Helge Mathisen, Rune Norheim, Elkem AS Technology (Norway); Reinhardt Willsch, Markus Schmidt, Institut für Photonische Technologien e.V. (Germany)

We tested the long term stability of first order Sapphire Fiber Bragg gratings (SFBG) at 1400°C for a period of 28 days in air. During the whole period temperatures detected by the SFBG differed less than ±2K°C from the temperatures measured by a type B thermocouple. The spectra at the beginning and the end of the installation were identical. The reliable practical application of wavelength-multiplexed two-grating SFBG arrays for quasi-distributed sensing at very high temperatures has been demonstrated.

P32/Paper 9157-330

Temperature characteristics of a high sensitive dual side hole fiber Jalal Sadeghi, Hamid Latifi, Shahid Beheshti Univ. (Iran, Islamic Republic of); Michal Murawski, Tomasz Nasiłowski, InPhoTech Ltd. (Poland); Paweł Mergo, Krzysztof Poturaj, Univ. of Maria Curie-Sklodowska (Poland); Farnood Mirkhosravi, Shahid Beheshti Univ. (Iran, Islamic Republic of)

A dual side hole fiber (DSHF) with a pair of large air holes is proposed for free transducer temperature sensing in the infrared region (1500–1600 nm). The results of birefringence measurement based on a sagnac interferometer showed the linear group birefringence is from 4.35×10-5 at 1500 nm, to 1.14×10-4 at 1600 nm, respectively. The group birefringence of DSHF leads to a group temperature sensitivity from 3.9nm/oc at 1501nm to 1nm/oc at 1595nm, respectively.

P33/Paper 9157-359

Performance of chirped-FBG Fabry-Perot interferometer sensor in pulse-position modulation scheme: large-signal operation Shingo Tekuramori, Makoto Takeuchi, Ryotaro Uchimura, Osamu Tsukida, Atsushi Wada, Satoshi Tanaka, Nobuaki Takahashi, National Defense Academy (Japan)

Operation of an optical fiber sensor based on an in-fiber Fabry-Perot interferometer using chirped fiber Bragg gratings is examined in the pulse-position modulation scheme, especially for mechanical vibration measurement. Emphasis is placed on the ability to measure vibration of largerplitude. Although the magnitude of vibration that can be measured with a single Fabry-Perot resonance peak is rather limited, the limitation is expected to be overcome by use of multiple resonance peaks in the operation. The experiment with five resonance peaks shows the successful operation of the sensor and therefore the validity of the method proposed.

P34/Paper 9157-376

Detection of an extremely small mass with a dual-polarization fiber grating laser Yizhi Liang, Long Jin, Qiang Yuan, LingHao Cheng, Bai-Ou Guan, Jinan Univ. (China)

We demonstrate the ability of a fiber grating laser with dual-polarization, single-longitudinal-mode output to measure an extremely

small mass (or transverse load). The minimum detectable mass is 0.28 milligram by reducing the noise level of the output beat signal. P35/Paper 9157-388

Simple fabrication method for point temperature sensor probes using erbium ytterbium-coated optical fibres Erik P. Schartner, Tanya M. Monro, The Univ. of Adelaide (Australia)

We report on the development of a point temperature sensor, based on coating tellurite onto the tips of optical fibres. By doping the tellurite glass with rare earth ions such as erbium the tip of the fibre can act as a localized temperature sensor by monitoring the upconversion emission from the ions. This sensing geometry allows the temperature to be measured with good spatial resolution, while the strong response of the rare earth ions to changing temperature provides a temperature precision of 0.1-0.3 °C over the measured range.

P36/Paper 9157-394

Influence of quarter-wave retarder parameters on performance of fiber-optic current sensor Sergey M. Kostritskii, Yuri N. Korkishko, Vyacheslav A. Fedorov, Optolink RPC (Russian Federation); Vladimir P. Mitrokhin, Optolink RPC (Russian Federation), Photochemistry Ctr. (Russian Federation)

Temperature stability of magneto-optic sensor at a marked transient temperature gradient has been investigated. Our experimental study leads to the conclusion that the polarized gyro architecture with two quarter-wave retarders on the opposite sides of the fiber loop of Sagnac interferometer must be used to obtain a fiber-optic current sensor with the low-drift behavior.

P37/Paper 9157-400

Magnetic field sensor based on reflection spectrum measurement of fiber Bragg grating

Jingyi Yang, Xinyong Dong, Shangzhong Jin, China Jiliang Univ. (China); Chi Chiu Chan, Perry Ping Shum, Nanyang Technological Univ. (Singapore)

A novel magnetic field sensor by using an optical fiber Bragg grating (FBG) cascaded by a cleaved optical fiber end, which is face surrounded with magnetic fluid (MF), is experimentally demonstrated. Through Fresnel reflection (FR) of the fiber end face, side mode suppression ratio (SMSR) of reflection spectrum of the FBG is tuned by refractive index (RI) of the MF, which is sensitivity to the external magnetic field. As a result, magnetic field measurement is successfully achieved. Compared with previously reported methods based on FR of a fiber end only, it eliminates the influence of power level fluctuation of the optical source and therefore improves the measurement accuracy and stability. Furthermore, temperature can be measured simultaneously by monitoring wavelength shift of the FBG.

P38/Paper 9157-411

Characterization of Cerenkov radiation generated in silica and plastic optical fibers Kyoung Won Jang, Sang Hun Shin, Seon Geun Kim, Wook Jae Yoo, Konkuk Univ. (Korea, Republic of); Younghoon Ji, Korea Institute of Radiological and Medical Sciences (Korea, Republic of); Bongsoo Lee, Konkuk Univ. (Korea, Republic of)

In this study, gamma-ray induced Cerenkov radiation generated in silica and plastic optical fibers was measured in order to select an efficient optical fiber for producing Cerenkov radiation. The intensities and the spectra of Cerenkov radiation generated in the optical fibers were measured using a spectrometer. As the results, the intensities of Cerenkov radiation generated in silica and plastic optical fibers have peak wavelengths at approximately 500 nm. Also, the intensity of Cerenkov radiation obtained using a plastic wavelength shifting fiber was the highestong all sample optical fibers. P39/Paper 9157-416

Highly sensitive operation of intensity-based fiber-optic vibration sensor using cascaded long period fiber grating

Satoshi Tanaka, Osamu Tsukida, Makoto Takeuchi, Shingo Tekuramori, Ryotaro Uchimura, Atsushi Wada, Nobuaki Takahashi, National Defense Academy (Japan)

A highly sensitive fiber-optic vibration sensor is constructed by using a cascaded LPG based on an intensity modulation scheme. In the fabrication process, the cascaded LPG, which is composed of a pair of identical LPGs with a certain distance, is inscribed in a photosensitive single-mode fiber by means of a point-by-point technique using a KrF laser. Since the sensitivity of the intensity-based sensor depends on a gradient of the transmittance curve, the channeled spectrum of the cascaded LPG provides a highly sensitive detection. In the experiment, several kinds of cascaded LPGs are fabricated and highly sensitive vibration detection is demonstrated.

P40/Paper 9157-433

Study on the frequency response of static pressure compensated fiber laser hydrophone-theory and finite element simulation Faxiang Zhang, Xiaolei Zhang, Lujie Wang, Chang Wang, Laser Institute of Shandong Academy of Sciences (China)

This paper presents the study on the acoustic response of pressure compensated fiber laser hydrophones. Both a theoretical model and a finite-element model are developed to describe the acoustic response of the hydrophone. The proposed theoretical model has been preliminarily validated by an in air test of a hydrophone sample. A further analysis is also made to evaluate the sensor performances and the results offer reference for performance optimization.

P41/Paper 9157-438

Improved fibre optic acoustic sensors for partial discharge in elastomeric insulations Philipp Rohwetter, Chaiyaporn Lothongkam, Wolfgang R. Habel, Bundesanstalt für Materialforschung und -prüfung (Germany); Gerd Heidmann, Institut für Photonische Technologien e.V. (Germany); Daniel Pepper, Beuth Hochschule für Technik Berlin (Germany)

Partial discharge in elastomeric high voltage insulations is a major reason for device failure. The special challenges of the high voltage environment limit the use of conventional acoustic emission sensors. Fibre-optic sensors can cope with these challenges thanks to their optical sensing principle and the use of all-dielectric materials. In this contribution, improvements to a previously introduced design of ultrasonic fibre-optic acoustic partial discharge sensors for elastomeric insulations are presented. The improved performance of fibre-optic acoustic sensors in detecting AC partial discharge is demonstrated. Furthermore, their ability to detect low-level damage processes in elastomeric insulation under DC dielectric stress is shown to outperform the highly sensitive electrical detection method. P42/Paper 9157-474

Reflection-based phase-shifted long-period fiber grating for cryogenic temperature measurements Raquel Martins, Instituto Politécnico de Viana do Castelo (Portugal); José Monteiro, FiberSensing (Portugal); Paulo Caldas, Instituto Politécnico de Viana do Castelo (Portugal); José Luís C. Santos, Univ. do Porto (Portugal); Gaspar M. Rego, Instituto Politécnico de Viana do Castelo (Portugal)

In this work, we propose a compact sensor head to perform cryogenic temperature measurements based on a long-period fiber grating. The presented configuration enables the sensor to be interrogated in reflection since a phase-shifted is produced by Fresnel reflection on the end-face of the fiber, cleaved at a quarter-period separation distance from the end of the grating. P43/Paper 9157-491

Measurements of laser-induced thermoelastic deformation using all-fiber heterodyne interferometer SeongJun Park, Jonghyun Eom, Gwangju Institute of Science and Technology (Korea, Republic of); Lee Chang Su, The Univ. of Suwon (Korea, Republic of); Byeong Ha Lee, Gwangju Institute of Science and Technology (Korea, Republic of)

We report an all-fiber heterodyne interferometer for the measurements of laser-induced thermoelastic deformation to estimate the Gruneisen coefficient and the optical attenuation depth of a sample. The system comprises a Q-switched Nd-YAG laser providing a nanosecond excitation pulse and an all-fiber heterodyne interferometer that measures the induced displacement of the sample surface. To evaluate the system, phantom experiments were carried out with various gelatin-based models. The results show that the attenuation depth and Gruneisen coefficient of the phantoms were about 4.256 mm and 0.568, respectively. In addition, increase of the weight fraction of gelatin led increase in the Gruneisen coefficient.

P44/Paper 9157-548

Evaluation of the optical switching characteristics of erbium-doped fibres for the development of a fibre Bragg grating sensor interrogator Nikos A. Stathopoulos, Stylianos P. Savaidis, Technical Education Institue of Piraeus (Greece); Stephen W. James, Paul B. Kirby, Ralph P. Tatam, Cranfield Univ. (United Kingdom)

A polling topology that employs optical switching based on the properties of erbium-doped fibres (EDFs) is used to interrogate an array of FBGs. The properties of the EDF are investigated in its pumped and un-pumped states and the EDFs’ switching properties are evaluated by comparing them with a high performance electronically controlled MEM optical switch. Potential advantages of the proposed technique are discussed.

P45/Paper 9157-549

Temperature and mechanical reliability of electrolytic fiber to metal joints for applications in fiber optic sensor Tomasz Stańczyk, InPhoTech Ltd. (Poland); Tadeusz Tenderenda, Lukasz Ostrowski, InPhoTech Ltd. (Poland), Military Univ. of Technology (Poland); Henrik Krisch, Krohne Messtechnik GmbH (Germany); Leszek R. Jaroszewicz, Military Univ. of Technology (Poland); Tomasz Nasiłowski, InPhoTech Ltd. (Poland), Military Univ. of Technology (Poland)

In this work we present an innovative method of connecting metal coated optical fibers with metal surfaces. The process is based on electrolytic reaction between copper and allows to obtain a robustand inflexible connection. Furthermore reliability tests of such fiber to metal joints have been performed, with the results of mechanical strength and temperature resistance tests presented. Additionally, as accelerated oxidation of copper at elevated temperatures is a major concern in long term temperature stability of the connection, we propose a method of slowing down the oxidation process with chemical nickel coating. Analysis of the obtained results allows us to predict that the investigated connection may find applications in various industrial optical sensors with special focus on harsh environments.

P46/Paper 9157-556

Transverse strain response of in-fibre Fabry-Perot microcavities Mark Manders, Stephen W. James, Ralph P. Tatam, Cranfield Univ. (United Kingdom)

In-fibre microcavity Fabry-Perot interferometers were constructed by splicing single mode fibre to polarisation maintaining photonic crystal fibre (PCF), with the air in the PCF pressurised to 5.000±0.005bar. The response to transverse load was characterised, along with the influence of rotational orientation and the repeatability of the fabrication process. It was found that the features of the channelled reflected spectrum exhibited a blue wavelength shift with increasing applied transverse load. P47/Paper 9157-560

New silica microspheres array sensor Marta S. Ferreira, José Luís C. Santos, INESC Porto (Portugal)

In this work a novel optical fiber sensor based on silica microspheres array is proposed. Different sensing heads are presented and compared, differing on the number of microspheres. These structures, ranging from arrays of one to five, are spliced in series. The sensor is subjected to different physical parameters, such as strain, temperature, refractive index and bending. Depending on the number of microspheres the sensitivities to strain and bending are different. The sensor also presents a high sensitivity to temperature of 20.3 pm/ºC. P48/Paper 9157-581

Optical strain sensor based on FPI micro-cavities produced by the fiber fuse effect Maria F. Domingues, Paulo Antunes, Instituto de Telecomunicações (Portugal); Nélia Alberto, Instituto de Telecomunicações (Portugal), TEMA- Ctr. for Mechanical Technology and Automation- NRD (Nanotechnology Research

Division) (Portugal), Aveiro Institute of Nanotechnology (Portugal); Rita Frias, Instituto de Telecomunicações (Portugal); Rute Ferreira, Univ. de Aveiro (Portugal); Paulo André, Instituto de Telecomunicações (Portugal)

In this work we present a cost effective strain sensor based on micro-cavities produced through the re-use of optical fibers destroyed by the catastrophic fuse effect. The strain sensor estimated sensitivity is 2.22 ±0.08 pm/µε. After the fuse effect, the damaged fiber becomes useless and, consequently, it is an economical solution for sensing proposes, when compared with the cavities produced using other complex methods. Also, the low thermal sensitivity is of great interest in several practical applications, allowing eluding cross-sensitivity with less instrumentation, and consequently less cost.

P49/Paper 9157-588

All-fiber sensor based on a metallic coated hybrid LPG-FBG structure for thermal characterization of materials Gleison E. da Silva, Univ. de São Paulo (Brazil); Paulo S. A. Caldas, INESC Porto (Portugal); Josemir C. Santos, Univ. de São Paulo (Brazil); José Luís C. Santos, INESC Porto (Portugal)

All-fiber hot-wire needle probe concept to measure the thermal properties of materials, particularly the thermal conductivity, based on a metallic coated hybrid LPG-FBG structure

P50/Paper 9157-594

Optical fiber refractive index sensor with reduced thermal sensitivity based on Superimposed Long-Period Gratings Gleison E. da Silva, Univ. de São Paulo (Brazil); Paulo S. A. Caldas, INESC Porto (Portugal); Josemir C. Santos, Univ. de São Paulo (Brazil); José Luís C. Santos, INESC Porto (Portugal)

Optical Fiber Refractive Index Sensor with Reduced Thermal Sensitivity based on Superimposed Long-Period Gratings inscribed by electric arc method in standard fiber. P51/Paper 9157-606

Longitudinal spatial characterisation of optical fibre erbium distributed feedback laser under the motion of steady magnetic field Yuan Yao, Central China Normal Univ. (China), Univ. of Strathclyde (United Kingdom); Gordon M. H. Flockhart, Univ. of Strathclyde (United Kingdom)

The spatial sensitivity of an erbium doped optical fibre distributed feedback (DFB) laser to an external magnetic field is reported. Intrinsic birefringence of the laser cavity allows lasing in two orthogonal modes. The polarisation beat frequency between these modes is sensitive to magnetic fields aligned along the axis of the optical fibre due to the Faraday effect. The interaction of magnetic field, generated by a permanent magnet, with the spatial mode profile of the laser is investigated. Experimental measurements show a 3.82 MHz change in the beat frequency when a permanent magnet is scanned along the fibre laser. P52/Paper 9157-620

Fabry-Perot cavity hydrostatic pressure sensors Lidia Carvalho, Paulo Roriz, INESC Porto (Portugal); J. Simoes, Univ. de Aveiro (Portugal); José Santos, Orlando Frazão, INESC Porto (Portugal)

Interferometric fiber optic based sensors, namely those based on the Fabry-Perot (F-P) configuration seem very attractive for biomechanical and biomedical applications. The present study is focused on the proof of concept of two developed F-P based sensors, for high and low pressure measurements of fluids. For low pressure sensor, it was used a polymeric diaphragm in a microstrutured fiber. It was obtained a good agreement between wavelength shift and the pressure, for the two tested sensors.

P53/Paper 9157-626

Suppression of polarization instability in optical pulse correlation remote sensing Mifang Lu, Hirokazu Kobayashi, Kochi Univ. of Technology (Japan); Koji Nonaka, Kochi Univ. of Technology (Japan), Development Ctr. for Children's Future (Japan)

We have proposed an optical pulse correlation remote sensing technique, which has the advantages of high accuracy and good response linearity. To eliminate the impact of polarization fluctuation on sensing signals, we use a polarization scrambled pulse train (PSP), in which the polarization state of each pulse is randomized. We measure the stability of sensing signal under polarization fluctuation in optical pulse correlation sensing with the PSP light and obtain good stability. Moreover, we demonstrate tensile strain measurement using the optical pulse correlation sensing with the PSP and confirm the linear response to the tensile strain even under polarization changing.

P54/Paper 9157-630

High sensitivity side-polished multimode fiber based refractometer Huanbiao Gan, Hongbo Gan, Jun Zhang, Zhe Chen, Jieyuan Tang, Yunhan Luo, Jianhui Yu, Zhigang Zang, Huihui Lu, Jinan Univ. (China)

We have investigated the influence of side-polished multimode fiber (SPMMF) core diameters D and residual radius R (the minimum distance between side-polished surface and the center of multimode fiber) on the sensitivity of a SPMMF based refractometer. We show that the residual radius has significant influence on the refractive index (RI) sensitivity but the core diameter does not. A refractometer with a lower SPMMF core diameter has a higher sensitivity. Experimental investigations achieved a maximum sensitivity of 1815 dB/RIU (refractive index unit) for a refractive index range from 1.342 to 1.437 for a refractometer with a SPMMF core diameter of 50 μm.

P55/Paper 9157-649

Sensing with metallic nanowires? Pedro Fernandes, Univ. do Porto (Portugal); Ivo T. Leite, INESC TEC (Portugal); José Miguel Teixeira, Univ. do Porto (Portugal); A. Hierro-Rodríguez, Univ. do Porto (Portugal), INESC TEC (Portugal); João P. Araújo, Univ. do Porto (Portugal); Ariel Guerreiro, INESC TEC (Portugal)

In this work we show numerically the potential of using a metamaterial constituted by ordered arrays of silver nanowires as a sensor for refractive index changes of a surrounding dielectric medium. The results show a strong dependence of the reflectance spectrum on the refractive index of the dielectric medium. P56/Paper 9157-27

Control of the strain sensitivity using a suspended core photonic crystal fiber sensing head Sergio Rota-Rodrigo, Manuel López-Amo, Univ. Pública de Navarra (Spain); Jens Kobelke, Kay Schuster, Institut für Photonische Technologien e.V. (Germany); Jose Luis Santos, Orlando Frazão, INESC Porto (Portugal), Univ. do Porto (Portugal)

In this work a strain sensor based on a suspended core fiber is proposed. The sensor comprises a suspended core PCF between SMFs and is based on the multimode interference generated in these transitions. A strain sensitivity study for different sensing heads and stage separation lengths was carried out showing a sensitivity of -2.42 pm/ue for the best case. Also the sensing head was tested for curvature and temperature, showing in the first case that it is insensitive to curvature effects, and secondly, that for small sensor lengths it was insensitive to temperature variations. P57/Paper 9157-139

Temperature-insensitive Sagnac-type optical current transformer Kin'ichi Sasaki, Masao Takahashi, Yukihisa Hirata, Toshiba Corp. (Japan)

We estimated the influence of polarization crosstalk in a Sagnac-type optical current transformer (OCT) against sensor sensitivity, and confirmed that temperature dependence of Faraday effect is canceled out by controlling the extinction ratio of transmission fiber with temperature change. Based on the above evaluation, we developed a temperature compensation element (TCE) consisting of metal-coated PM fiber. Its extinction ratio varies with temperature because of the difference between the linear expansions of metal and fiber. The ratio error of OCT using this TCE in the temperature range from -40°C to 80°C was within 0.1%, and satisfied the required accuracy for IEC 60044-8 class 0.2S.

P58/Paper 9157-159

V-groove all-fiber intermodal Mach-Zehnder interferometer and its high-temperature sensing application Zhen Yin, Youfu Geng, Xuejin Li, Xiaoling Tan, Rong Gao, Shenzhen Univ. (China)

We demonstrate a novel V-groove all-fiber intermodal Mach-Zehnder interferometer fabricated by CO2 laser irradiation on a standard single-mode fiber. The high order cladding modes are excited due to the special V-groove structure. A high temperature sensitivity (114.09 pm/oC at 500 oC) is obtained by monitoring the wavelength shift of the interference spectrum, and it shows a good repeatability of temperature response in both the heating and the cooling processes. This type of sensor has the features of compact size, high sensitivity, low cost, and relative easy to fabricate.

P59/Paper 9157-199

Simultaneous strain and temperature measure based on a single suspended core photonic crystal fiber Sergio Rota-Rodrigo, Manuel López-Amo, Univ. Pública de Navarra (Spain); Jens Kobelke, Kay Schuster, Institut für Photonische Technologien e.V. (Germany); José Luis C. Santos, Orlando Frazão, INESC Porto (Portugal)

In this work a simultaneous strain and temperature sensor based on a suspended core fiber is proposed. The sensor comprises a 3mm suspended core PCF between SMFs and is based on the combination of two multimodal interferences with different frequency fringe patterns. The interference of the both signal has different sensitivity responses to strain and temperature. Thought a low-pass frequency filtering of the detected spectrum, the wavelength shift of the two interferences can be measured allowing the discrimination of strain and temperature simultaneously. The resolutions of this sensor are 0.45 ºC and 4.02 microstrains.

P60/Paper 9157-252

Multiplexed EFPI sensors with ultra-high resolution Nikolai A. Ushakov, Leonid B. Liokumovich, St. Petersburg State Polytechnical Univ. (Russian Federation)

An investigation of performance of multiplexed displacement sensors based on extrinsic Fabry-Perot interferometers has been carried out. We have considered serial and parallel configurations and analyzed the issues and advantages of the both. We have also extended the previously developed baseline demodulation algorithm for the case of a system of multiplexed sensors. Serial and parallel multiplexing schemes have been experimentally implemented with 3 and 4 sensing elements, respectively. For both configurations the achieved baseline standard deviations were between 30 and 200 pm, which is, to the best of our knowledge, more than an order less than any other multiplexed EFPI resolution ever reported.

P61/Paper 9157-266

Fabrication and characterization of spun HiBi PCF fibers for current sensing applications Ivo M. Nascimento, INESC Porto (Portugal); Giancarlo Chesini, Univ. Estadual de Campinas (Brazil); Angela C. S. Brígida, Univ. Federal do Pará (Brazil); Juliano G. Hayashi, Univ. Estadual de Campinas (Brazil); José M. Baptista, Univ. da Madeira (Portugal), INESC Porto (Portugal); João C. W. Costa, Univ. Federal do Pará (Brazil); M. A. Martinez, Ctr. Federal de Educação Tecnológica Celso Suckow da Fonseca (Brazil); Pedro A. S. Jorge, INESC Porto (Portugal); Cristiano M. B. Cordeiro, Univ. Estadual de Campinas (Brazil)

In this paper three highly birefringent (HiBi) spun photonic crystal fibers (PCF) are fabricated and their performance are characterized for electrical current measurement. These fibers are tested by coiling them around an electric conductor using three distinct winding diameters with different turns. The results present a very good linear relation with the current and its sensitivity depends on the winding diameter and on the number of turns. For the larger winding diameter, the fiber with lower circular pitch had higher sensitivity and for the smaller winding diameter the best sensitivity result was for the fiber with higher circular pitch.

P62/Paper 9157-332

Giant-area fiber-optic gyroscope with Raman-based temperature sensing for metrological applications Gabriele Bolognini, Consiglio Nazionale delle Ricerche (Italy); Cecilia Clivati, Istituto Nazionale di Ricerca Metrologica (Italy); Giovanni Costanzo, Politecnico di Torino (Italy); Matteo Frittelli, Filippo Levi, Alberto Mura, Istituto Nazionale di Ricerca Metrologica (Italy); Stephan Schiller, Heinrich-Heine-Univ. Düsseldorf (Germany); Davide Calonico, Istituto Nazionale di Ricerca Metrologica (Italy)

In this paper we present a giant-area fiber-optic gyroscope (GAFOG) combining a Raman distributed temperature sensor (RDTS) for metrological monitoring of Earth rotation rate fluctuations. The GAFOG exhibits sensitivity limits in Earth rotation sensing associated to temperature variations along the fiber. Distributed temperature measurements providing an accurate fiber temperature mapping, enable tracking of the signal phase drifts. This allows reduction of the phase noise at low Fourier frequencies, and a corresponding enhancement of the Earth rotation rate variation sensitivity beyond the currently achieved 2•nrad/s for integration times of 1000 s.

P63/Paper 9157-368

Temperature-insensitive strain sensor based on in-line Fabry-Perot interferometer Yiping Wang, Shen Liu, Changrui Liao, Zhengyong Li, Qiao Wang, Guolu Yin, Jun He, Bing Sun, Jing Zhao, Jian Tang, Shenzhen Univ. (China)

We demonstrated a high-sensitivity strain sensor based on an in-line Fabry-Perot interferometer with an air cavity whose was created by splicing together two sections of standard single mode fibers. The sensitivity of this strain sensor was enhanced to 6.02 pm/με by improving the cavity length of the Fabry-Perot interferometer by means of repeating arc discharges for reshaping the air cavity. Moreover, such a strain sensor has a very low temperature sensitivity of 1.06 pm/oC, which reduces the cross-sensitivity problem between tensile strain and temperature.

P64/Paper 9157-387

An all optical fiber frequency reference using digital interferometry Malcolm B. Gray, Terry McRae, National Measurement Institute of Australia (Australia); Silvie Ngo, Daniel Shaddock, Australian National Univ. (Australia); Magnus T. L. Hsu, National Measurement Institute of Australia (Australia)

We use digitally enhanced heterodyne interferometry to measure the stability of optical fiber laser frequency references. Suppression of laser frequency noise by over four orders of magnitude is achieved using post processing time delay interferometry. This approach avoids dynamic range and bandwidth issues that can occur in feedback stabilization systems. Thus long fiber lengths may be used resulting in better frequency discrimination, a reduction in spatially uncorrelated noise sources and an increase in

-static frequencies as low as 20 mHz. P65/Paper 9157-390

Sensitivity enhancement of Faraday effect based heterodyning fiber laser magnetic field sensor with the assistance of CO2-laser treatment Linghao Cheng, Jianlei Han, Long Jin, Zhenzhen Guo, Bai-Ou Guan, Jinan Univ. (China)

We have proposed a novel magnetic field sensor based on orthogonally-polarized dual-frequency fiber laser and Faraday effect. In this paper, we propose a method to enhance the sensitivity of such Faraday effect based heterodyning fiber laser magnetic field sensor by tuning the intra-cavity intrinsic linear birefringence. We demonstrate that the sensitivity to magnetic field intensity is inversely proportional to the linear birefringence. A CO2-laser treatment is therefore proposed to tune the intra-cavity linear

birefringence. With CO2-laser treatment to lower the intra-cavity linear birefringence, the sensitivities of heterodyning fiber laser sensors to magnetic field can be enhanced.

P66/Paper 9157-454

Temperature sensor with enhanced sensitivity by cascaded fiber optic Sagnac loops Li-Yang Shao, Yuan Luo, Zhiyong Zhang, Xihua Zou, Bing Luo, Wei Pan, Lianshan Yan, Southwest Jiaotong Univ. (China)

We demonstrate a temperature sensor with ~ 9 times sensitivity enhancement that consists of two cascaded sagnac interferometers and works analogously to a Vernier scale. Experimental results show that the temperature sensitivity is increased from -1.46 nm/oC based on single sagnac configuration to -13.36nm/oC. P67/Paper 9157-477

Refractive index insensitive temperature sensor based on hollow annular core fiber Mach-Zehnder interferometer Yaxun Zhang, Ai Zhou, Quan Xu, Boyang Qin, Zhihai Liu, Harbin Engineering Univ. (China)

We propose a refractive index insensitive temperature sensor based on hollow annular core fiber (HACF) Mach-Zehnder interferometer (MZI). The HACF is composed of a large-diameter air hole, an annular core around the air hole and a cladding. The MZI is fabricated by inserting a short section of the HACF between two short multimode fibers, and the interference occurs between the light beams transmitting along the air hole and the annular core of the HACF. Experimental results show that the MZI is insensitive to external refractive index and has temperature sensitivity of 30 pm/°C. P68/Paper 9157-479

Ultra-high sensitive temperature sensor based on multimode fiber Mach-Zehnder interferometer Ai Zhou, Yaxun Zhang, Yuanyuan Yang, Jun Yang, Zhihai Liu, Harbin Engineering Univ. (China)

We propose an ultra-high sensitive temperature sensor based on multimode fiber Mach-Zehnder interferometer (MZI). The MZI is composed of a short MMF inserting between another two MMFs with large lateral offset. The sensing head is packaged in a capillary which is filled with glycerol-water solution. At the offset splice interface, part of the light in the lead-in MMF is coupled into the glycerol solution and the remainder propagates along the cladding of the sensing MMF. Due to the large thermo-optic coefficient of the glycerol solution, the transmission spectrum of the MZI shift quickly with temperature variation. Experimental results show that the temperature sensitivity is as high as 8.23 nm/°C.

P69/Paper 9157-496

Polarimetric DBR fiber laser sensor for strain-temperature discrimination Luis Rodriguez-Cobo, M. Angeles Quintela, Ismail Laarossi, Jose Miguel Lopez-Higuera, Univ. de Cantabria (Spain)

A polarimetric Distributed Bragg Reflector (DBR) laser sensor in a low birefringent Er-doped fiber has been proposed. The spectral overlap of two uniform fiber Bragg gratings (FBG) has been employed as filtering technique to achieve a Single Longitudinal Mode (SLM) regime. By measuring the RF beat frequency between the two orthogonal polarized lasing modes and the absolute wavelength of one mode, both strain and temperature has been determined simultaneously. P70/Paper 9157-500

In-line Mach-Zehnder interferometer based on a dissimilar-doping dual-core fiber for high sensitivity strain and temperature sensing Hugo F. Martins, INESC Porto (Portugal), Univ. do Porto (Portugal), Univ. de Alcalá (Spain); Jörg Bierlich, Katrin Wondraczek, Sonja Unger, Jens Kobelke, Kay Schuster, Institut für Photonische Technologien e.V. (Germany); Miguel Gonzalez-Herraez, Univ. de Alcalá (Spain); Orlando Frazão, INESC Porto (Portugal), Univ. do Porto (Portugal)

A dual-core fiber in which one of the cores is doped with Germanium and the other with Phosphorus is used as an in-line Mach-Zehnder (MZ) interferometer to perform high sensitivity strain and temperature sensing. Opposite sensitivities for high and low wavelength peaks were demonstrated when strain was applied. To our knowledge this is the first time that such behavior is demonstrated using this type of in-line MZ interferometer based on a dual-core fiber. A sensitivity of (78±2) pm/με, between 0-950 με and (1380±20) pm/ºC between 45 and 80ºC is demonstrated. It was also demonstrated that it is possible to use this configuration for simultaneous measurement of strain and temperature and a matrix equation to calculate them was given. P71/Paper 9157-521

Interferometric filtering of the excess relative intensity noise of the broadband source of a fiber-optic gyroscope Joachin Honthaas, IXBLUE (France); Jean-Jacques Bonnefois, IXBLUE / IXSPACE (France); Eric Ducloux, Herve Lefevre, IXBLUE (France)

We present a new method of reduction of the excess RIN (relative intensity noise) of the broadband source of a fiber-optic gyroscope (FOG). It is based upon the use of an interferometric filter which reduces the excess RIN at the proper frequency of the sensing coil. We demonstrate that a fiber-optic ring resonator can provide a RIN power density reduction (PSD) of 18dB allowing the FOG to operate near the photon-noise limit.

P72/Paper 9157-534

Influence of spin manufacturing process on properties of the spun single mode fiber Jianxiang Wen, Shanghai Univ. (China)

Influence of spin manufacturing process on properties of the spun single mode fiber is investigated, a unidirectional spinning preform during the drawing process. The drawing speed constant is 1 m/min. The results show that pitch of the spun fiber exists; that mode field diameter (MFD) is obviously smaller; that cutoff wavelength and polarization mode dispersion (PMD) are decreased significantly, and then the loss is increased significantly when the spun fiber pitch is lower than 1.5 mm. It is very important for the fiber-optic gyroscope and fiber-optic current sensors to optimize spinning design to obtain relatively good spun fibers.

P73/Paper 9157-535

Open cavity Fabry-Pérot interferometric refractometer based on C-shaped fiber Chuang Wu, Bai-Ou Guan, Jinan Univ. (China)

We demonstrated an in-line open cavity Fabry–Pérot interferometer (FPI) for liquid refractive index sensing with linear response and high sensitivity. The FPI was fabricated by splicing a short piece of C-shaped fiber (tens of micrometers) between two standard single-mode fibers. The refractive index response of the FPI was characterized by ethanol-water mixtures in the range of 1.33 to 1.36, and a high sensitivity of 1294 nm/RIU at the wavelength of 1550 nm was achieved. The sensor was used to measure the thermo-optic coefficient of pure water, and the results agree well with the literature.

P74/Paper 9157-579

Optical fiber sensor of partial discharges in High Voltage DC experiments Iago Búa-Núñez, Univ. Carlos III de Madrid (Spain); Carlos Gustavo Azcárraga-Ramos, Univ. degli Studi di Bologna (Italia); Julio Enrique Posada-Roman, José Antonio García-Souto, Univ. Carlos III de Madrid (Spain)

A setup simulating High Voltage DC (HVDC) transformers barriers was developed to demonstrate the effectiveness of an optical fiber (OF) sensor in detecting partial discharges (PD) under these peculiar conditions. Different PD detection techniques were compared: electrical methods, and acoustic methods. Standard piezoelectric sensors (R15i-AST) and the above mentioned OF sensors were used for acoustic detection. The OF sensor was able to detect PD acoustically with a sensitivity better than the other detection methods. The multichannel instrumentation system was tested in real HVDC conditions with the aim of analyzing the behavior of the insulation (mineral oil/pressboard).

P75/Paper 9157-625

Thermal strain along optical fiber in lightweight composite FOG: Brillouin-based distributed measurement and finite element analysis Shu Minakuchi, Teruhisa Sanada, Nobuo Takeda, The Univ. of Tokyo (Japan); Shinji Mitani, Tadahito Mizutani, Yoshinobu Sasaki, Keisuke Shinozaki, Japan Aerospace Exploration Agency (Japan)

Thermal strain significantly affects stability of fiber optic gyroscope (FOG) performance. This study investigates thermal strain development in a lightweight carbon fiber reinforced plastic (CFRP) FOG under thermal vacuum condition simulating space environment. First, we measure thermal strain distribution along an optical fiber in a CFRP FOG using a Brillouin-based high-spatial resolution system. The key strain profile is clarified and the strain development is simulated using finite element analysis. Finally, several constituent materials for FOG are quantitatively compared from the aspect of the maximum thermal strain and the density, confirming the clear advantage of CFRP.

P76/Paper 9157-642

Speckle POF sensor for detecting vital signs of patients Mauro Lomer, Luis Rodriguez-Cobo, Pablo Revilla, Gumercindo Herrero, Ftancisco Madruga, Jose Miguel Lopez-Higuera, Univ. de Cantabria (Spain)

In this work, both arterial pulse and respiratory rate have been successfully measured based on changes in speckle patterns of multimode fibers. Using two fiber-based transducers, one located on the wrist and another in the chest, both disturbances were transmitted to the fiber, varying the speckle pattern. These variations of the speckle pattern were captured using a commercial webcam and further processed using different methods. The achieved results have been presented and the simultaneous monitoring of both vital signs has been also discussed. The feasibility to use the proposed sensor system for this application is demonstrated. P77/Paper 9157-667

Stress-based mechanisms in polymer mPOFs for fibre optic sensing Gaizka Durana, Oskar Arrizabalaga, Gotzon Aldabaldetreku, Maria Asunción Illarramendi, Joseba Zubia, Univ. del País Vasco (Spain)

The polarisation state of light may be exploited in single-mode polymer mPOFs for sensing purposes. The bend-induced birefringence varies linearly with the inverse square of the bend radius, whereas the twist-induced polarisation rotation varies linearly with the fibre twist angle. Both effects are highly reproducible and show higher sensitivity than their glass counterparts.

P78/Paper 9157-636

Ultra-short DBR fiber laser based sensor for arterial pulse monitoring

Qizhen Sun, Jianghai Wo, He Wang, Deming Liu, Huazhong Univ. of Science and Technology (China)

An ultra-short DBR fiber laser based device for arterial pulse wave monitoring is proposed and demonstrated. As the sensing element, the 10mm length laser cavity is mounted onto a soft plastic plate and then embedded into textile. Deformation of the textile, involving the transverse force subjected by the laser cavity, is proportional to the vibration caused by the arterial pulse. The sensing principle is based on the linear relationship between the beat frequency of the laser and the transverse force. Laboratory studies demonstrate that the sensor could achieve real-time and accurate measurement of the weak and dynamical arterial pulse signal.

P79/Paper 9157-209

Fabrication of long period fiber gratings based on embedded-core hollow optical fiber Chunying Guan, Xing Zhong, Harbin Engineering Univ. (China); Xiaozhong Tian, Harbin Engineering Univ. (China), PetroChina Co. (China); Shuqiang Li, Libo Yuan, Harbin Engineering Univ. (China)

We propose and experimentally demonstrate a novel long period fiber grating (LPFG) in an embedded-core hollow optical fiber (ECHOF). Without the structural deformation of the air hole and the fiber core, the high-quality LPFG can be fabricated within a few scanning cycles by a high-frequency CO2 laser with a low energy density of 0.896J/mm2. The ECHOF LPFG reveals a high temperature sensitivity of 50.2 pm/°C and a low strain sensitivity of 0.4 pm/με. Due to the good performance and easy fabrication, the ECHOF LPFG will be important to develop novel in-fiber devices. P80/Paper 9157-222

Polarization characteristics of graphene-coated surface core fiber Chunying Guan, Shuqiang Li, Xing Zhong, Yize Shen, Libo Yuan, Harbin Engineering Univ. (China)

The polarization characteristics of graphene-coated surface core fibers are numerically analyzed. The effects of the chemical potential and the ellipticity of the fiber core on the loss spectrum of fundamental mode of graphene-coated surface core fibers are investigated by using the finite element method (FEM). The surface core fiber with a semi-elliptical core is also discussed. P81/Paper 9157-254

Advanced fabrication and calibration of high-temperature sensor elements based on sapphire fiber Bragg gratings Tino Elsmann, Tobias Habisreuther, Manfred Rothhardt, Reinhardt Willsch, Hartmut Bartelt, Institut für Photonische Technologien e.V. (Germany)

In this paper, improved fabrication and calibration techniques of Fiber Bragg Gratings (FBG) for very high temperature sensing applications up to more than 1500 °C will be presented. The fibers used are single crystalline sapphire fibers, which are applicable in such high temperature ranges due to their high melting point at 2040 °C and their extreme thermal stability. The inscription of the FBGs was performed by the second harmonic wave of a Ti:Sa-femtosecond laser system. With pulses of 400 nm wavelength first order gratings could be achieved. Using a two-beam phase mask interferometer, grating arrays within a wide spectral range have been fabricated with only one phase mask and without additional calibration routine. The inscribed grating arrays were wavelength-calibrated using a reference FBG, and their temperature sensitivity was evaluated. P82/Paper 9157-256

Novel sensing concept based on optical Tamm plasmon Weili Zhang, Fen Wang, Yunjiang Rao, Jiang Yao, Univ. of Electronic Science and Technology of China (China)

This paper proposes a novel concept of refractive index sensing using a high-refractive-index-contrast optical Tamm plasmon (OTP) structure, i.e., an air/dielectric alternate-layered distributed Bragg reflector (DBR) coated with metal. In the reflection spectrum of the structure, a dip related to the formation of OTP appears. The dip wavelength and reflectivity are sensitive tobient refractive index, which provide a potential way of refractive index sensing with a large measuring range and high sensitivity.

P83/Paper 9157-262

Displacement measurement based on cross-phase modulation of orthogonally polarized sinusoidal optical signals Chams Baker, Xiaoyi Bao, Univ. of Ottawa (Canada)

We present a novel approach for short, medium, and long range displacement measurement. This approach is based on the interrogation of the relative phase-shift between two orthogonally polarized sinusoidal optical signals through cross-phase modulation. Displacement determines the power of the side-band generated from cross-phase modulation. Displacement measurement over a range of 12 mm with sub millimeter resolution is demonstrated.

P84/Paper 9157-283

Short cavity active mode locking fiber laser for optical sensing and imaging Hwidon Lee, Myung Yung Jeong, Chang-Seok Kim, Pusan National Univ. (Korea, Republic of); Jun Geun Shin, Byeong Ha Lee, Tae Joong Eom, Gwangju Institute of Science and Technology (Korea, Republic of)

We demonstrate a highly linear wavenumber- swept active mode locking (AML) fiber laser for optical sensing and imaging without any wavenumber-space resampling process. In this all-electricL wavenumber-swept mechanism, a conventional wavelength selection filter is eliminated and, instead, the suitable programmed electric modulation signal is directly applied to the gain medium. Various types of wavenumber (or wavelength) tunings can be implemented because of the filter-less cavity configuration. Therefore, we successfully demonstrate a linearly wavenumber-sweptL fiber laser with 26.5 mW of output power to obtain an in-vivo OCT image at the 100 kHz swept rate.

P85/Paper 9157-289

Microstructured fibres ultraviolet sources for sensing applications Zbigniew Holdynski, Marek Napierala, Michal Szymanski, Michal Murawski, Military Univ. of Technology (Poland), InPhoTech Ltd. (Poland); Pawel Mergo, Univ. of Maria Curie-Sklodowska (Poland); Pawel Marc, Leszek R. Jaroszewicz, Military Univ. of Technology (Poland); Tomasz Nasiłowski, Military Univ. of Technology (Poland), InPhoTech Ltd. (Poland)

We show a new possibility for extension of supercontinuum spectrum generated in photonic crystal fibre towards the UV light. To do so, we use four wave mixing and cross phase modulation nonlinear effects as well as interaction of fundamental mode with higher order modes. It is shown that a few modes operation and proper dispersion profiles of these modes give a possibility of nonlinear effects optimization and thus improvement of UV generation. The advantage of presented solution is the employment of cascaded nonlinear interactions inside one microstructured fibre. P86/Paper 9157-310

Regeneration of tilted fiber Bragg gratings Romain Cotillard, Guillaume Laffont, Pierre G. Ferdinand, Commissariat à l'Energie Atomique (France)

Regeneration of Tilted Fiber Bragg Gratings photowritten in a singlemode SMF-28e fiber is investigated. Three tilted FBGs, with respectively 0°, 4° and 8° external tilt angles are annealed according to a conventional high temperature regeneration protocol. We monitor the evolution of distinct spectral features during the thermal annealing process. We also propose a method in order to follow the regeneration process of tilted FBG, without focusing on individual spectral resonances. Regeneration of tilted FBGs presents numerous interests for the realization of high temperature sensors and devices, but also to improve their resistance to preliminary manufacturing processes requiring high temperature steps.

P87/Paper 9157-314

First order fiber Bragg grating inscription with femtosecond laser and reflection wavelengths from visible to infrared Martin Becker, Tino Elsmann, Anka Schwuchow, Manfred Rothardt, Sebastian Dochow, Hartmut Bartelt, Institut für Photonische Technologien e.V. (Germany)

Here we report on the inscription of fiber Bragg gratings with two beam interferometry and deep ultraviolet femtosecond laser exposure. This allows to target first order Bragg grating reflections from 2000 nm down to 660 nm without the need for germanium doping or hydrogen loading. The grating in the visible region is remarkable because it bases on a femtosecond laser induced structural size around 110 nm.

P88/Paper 9157-360

Ultrahigh resolution optical spectrometry based on Brillouin dynamic grating Yongkang Dong, Taofei Jiang, Lei Teng, Harbin Institute of Technology (China); Hongying Zhang, Harbin Univ. of Science and Technology (China); Liang Chen, Xiaoyi Bao, Univ. of Ottawa (Canada); Zhiwei Lv, Harbin Institute of Technology (China)

We demonstrate an ultrahigh resolution optical spectrometry based on Brillouin dynamic grating (BDG). Taking advantage of creating a long grating in an optical fiber, an ultra-narrow bandwidth optical filter is realized by operating a BDG in a long single-mode fiber (SMF), and the optical spectrometry is performed by sweeping the center wavelength of the filter through swept-tuned laser. In experiment, a 4-fm (0.5 MHz) spectral resolution is achieved by operating a BDG in a 400-m SMF, and the wavelength coverage can be readily extended to C+L band with a commercial tunable laser.

P89/Paper 9157-408

Strain sensitivity enhancement for FBG sensors by all-optical frequency chirp magnification with high-order cascaded FWM Jiangbing Du, Xinyu Fan, Qingwen Liu, Zuyuan He, Shanghai Jiao Tong Univ. (China)

High-order and cascaded four-wave-mixing (FWM) is utilized for enhancing the strain sensitivity of an FBG sensor based on all-optical frequency chirp magnification. 7.6-pm/με strain sensitivity is obtained for a conventional FBG sensor, which has been magnified by a factor of six.

P90/Paper 9157-418

Highly stable single-wavelength and broadband random fiber lasers Weili Zhang, Shi Wei Li, Yunjiang Rao, Ye Yu Zhu, Zi Nan Wang, Jin Li, Univ. of Electronic Science and Technology of China (China)

Highly stable single-wavelength and broadband random fiber lasers are reported as potential light sources for use in photonic sensing, for the first time, which are based on the hybrid pumping with mixing of Er-doped fiber (EDF) and single-mode fiber (SMF). P91/Paper 9157-422

High-sensitivity fiber optic accelerometer based on multilayer fiber coils Feng Peng, Jun Yang, Fei Gao, Harbin Engineering Univ. (China)

A high-sensitivity fiber accelerometer based on multilayer fiber coils is proposed. Acceleration sensing principle of the sensor is analyzed in theory, and with the finite element software, simulation model is built. Two kinds of fiber optic accelerometers with different multilayer fiber coils are designed, and the performance tests are conducted as well. Experimental results show that the sensitivity of accelerometer based on multilayer fiber coils can reach thousands rad/g, and the equivalent transfer coefficient between different layers in multilayer fiber coils is 0.39.

P92/Paper 9157-456

Supercontinuum generation in nonlinear fibers using high-energy figure-of-eight mode-locked fiber laser for SD-OCT application Bo Xu, Tsubasa Nagata, Shinji Yamashita, The Univ. of Tokyo (Japan)

Generation of flat and broadband supercontinum is demonstrated in an all fiber system using the high-energy noise-like pulses from a stable figure-of-eight fiber laser and nonlinear fibers. This SC source is successfully applied to the spectral domain optical coherence tomography. The axial resolution is significantly improved compared with the case of the superluminescent diode source. SD-OCT imaging is also demonstrated.

P93/Paper 9157-502

Optical power supply unit utilizing high power laser diode module developed for fiber laser pumping Akira Sakamoto, Fujikura Ltd. (Japan)

High power laser diode developed for fiber laser pumping is evaluated as a light source for an optical power supply unit. The output power of the newly developed laser diode module exceeds 15 W with 105 um core fiber. It is estimated that more than 1600 mW power supply can be achieved with the single emitter laser diode module and a polycrystalline silicon cell over 1 km away from the light source. This unit can be used for sensor nodes in the fiber sensor network. P94/Paper 9157-480

Al-doped optical fiber to enhance strain sensitivity of Brillouin based optical fiber sensors Yolande Sikali-Mamdem, Frederic Taillade, EDF R&D (France); Yves Jaouen, Renaud Gabet, Institut Telecom/Telecom ParisTech (France); Gautier Moreau, EDF R&D (France); Alexey Faustov, SCK CEN (Belgium); Guillaume Pilorget, Sylvie Delepine-Lesoille, ANDRA (France)

In order to meet application requirements, dependence of the Brillouin frequency shift to strain should be enhanced. We evaluated the influence of several optical fiber dopants on Brillouin scattering strain sensitivity. Based on a FEM-2D modeling, we developed a model for Brillouin gain spectrum and its strain sensitivity. Geometrical profile, doping composition and drawing conditions are taken into account. We show alumina is a very interesting dopant to enhance strain sensitivity in optical fibers. This result is experimentally validated: up to 0.0639MHz/µm/m is obtained with a 5.2mol% Al2O3 doped fiber. We expect to reach 0.1MHz/µm/m with 25mol% doping level.

P95/Paper 9157-481

Temperature characterisation of an optically interrogated Rogowski coil Grzegorz Fusiek, Philip Orr, Pawel Niewczas, Univ. of Strathclyde (United Kingdom)

An investigation into the performance of an optically-interrogated Rogowski coil over temperatures up to 80 °C is presented. Preliminary thermal tests reveal that the sensor response is temperature-dependent and the measurement errors are increased at higher temperatures. Compensation of temperature effects is, therefore, necessary in order for the sensors to meet the requirements of protection and metering classes specified by relevant IEC standards over the considered operating temperature range. This can, however, only be achieved when the utilised sensor interrogator is adapted to ensure sufficient resolution and accuracy from a generally low-output transducer. As such, the design of a new multiplexing, interferometric interrogation platform is also proposed in this paper.

P96/Paper 9157-501

Multi-core to 7 single-core-fibers fan-out device with multi-core fiber pigtail connector Koji Omichi, Katsuhiro Takenaga, Shoichiro Matsuo, Fujikura Ltd. (Japan); Kunimasa Saitoh, Hokkaido Univ. (Japan)

Multi-core to 7 single-core-fibers fan-out device with multi-core fiber pigtail connector is demonstrated to apply various types of multi-core fiber based sensor. Fused taper type fan-out device and SC type multi-core fiber connector are separately fabricated on each process. The fan-out device and the pigtail multi-core fiber are spliced each other by a specialty fiber fusion splicer. Comparatively low average insertion loss of 0.95 dB and sufficiently low reflectivity of less than -60 dB are achieved.

P97/Paper 9157-520

Single-polarization microfiber and resonator for sensing applications Fei Xu, Yan-qing Lu, Nanjing Univ. (China)

With a unique 3D geometry, a broadband polarizer and single-polarization resonator are demonstrated by wrapping a microfiber on a specialized rod with a hybrid polymer-metal-dielectric nanostructure, respectively. The polarizer has an extinction ratio of more than 20 dB over the spectra range of 450 nm. The resonator has a Q-factor of ~ 80,000 with excellent suppressing of polarization noise. By functionalizing the rod surface with nanoscale silver film and tuning the coil geometry, performances can be improved by optimizing those parameters. Such kind of miniature single-polarization microfiber and resonator are impossible to be realized by conventional fabrication process, and has the potential in gyro and current sensors.

P98/Paper 9157-530

A sub-micron plasmonic nano-resonator refractometer in metal-coated fiber taper Ming Ding, BeiHang Univ. (China), Univ. of Southampton (United Kingdom); Michalis N. Zervas, Gilberto Brambilla, Univ. of Southampton (United Kingdom)

Plasmonic slot nano-resonators (PSNR) embedded in gold-coated optical fiber tapers, can show strong three dimensional localization when optimized. Here the PSNR is used as a refractometer with small footprint. An average sensitivity of 66.7 nm/RIU and a resolvable index change of 1.5×10-4 for a resolvable wavelength change of 0.01 nm are obtained. P99/Paper 9157-543

Six microelectrodes assembly for tunable optical fibers Tomasz R. Woliński, Slawomir Ertman, Warsaw Univ. of Technology (Poland)

In last few years a noticeable progress in the field of electrically tunable optical fibers was observed. Guiding properties of such fibers can be easily changed with transverse electric field. The efficiency of tuning could be improved if not only intensity of the electric field by also its direction could be adjusted. In this paper we present a new electrode assembly consisting six cylindrical microelectrodes surrounding the tunable optical fiber. In such configuration six different directions of the electric field can be easily obtained. Moreover by using more sophisticated nonsymmetrical steering the direction of the electric field can be arbitrarily defined.

P100/Paper 9157-566

Pulse-Compression Optical Time Domain Reflectometer Shuo Yang, Weiwen Zou, Jianping Chen, Shanghai Jiao Tong Univ. (China)

This paper introduces a novel pulse-compression optical time domain reflectometer (OTDR) by utilizing linear frequency modulation (LFM) pulse-compression technology. The theoretical analysis shows that the spatial resolution is determined by the pulsed LFM sweeping range. A preliminary experiment of the pulse-compression OTDR is performed, providing 55 cm spatial resolution and 5.4 km measurement range under 2 μs pulse, 221 MHz LFM sweeping range, and 100 kHz linewidth laser diode. It is expectable to achieve a spatial resolution of less than 1 cm and dozens-kilometer measurement range by tens of GHz LFM sweeping ranges via microwave photonics. P101/Paper 9157-575

Performance of digital incoherent OFDR and prospects for optical fiber sensing applications Sascha Liehr, Bundesanstalt für Materialforschung und -prüfung (Germany); Nils Nöther, fibrisTerre GmbH (Germany); Milan Steffen, Bundesanstalt für Materialforschung und -prüfung (Germany); Oriol Gili, fibrisTerre GmbH (Germany); Katerina Krebber, Bundesanstalt für Materialforschung und -prüfung (Germany)

We propose a digital implementation of the incoherent optical frequency domain reflectometry (I OFDR) technique for precise backscatter measurement and optical fiber sensing applications. Specific performance parameters of the I-OFDR are discussed and compared to an analog vector network analyzer-based I-OFDR system. Improved sensitivity, dynamic range and signal stability of the digital I OFDR is presented and demonstrated by means of quasi-distributed length change measurement. P102/Paper 9157-590

Theoretical modeling of a Localized Surface Plasmon Resonance (LSPR) based fiber optic temperature sensor J. Francisco Algorri, B. García-Cámara, Univ. Carlos III de Madrid (Spain); A. García-García, Ciudad Univ (Spain).; V. Urruchi, J. M. Sánchez Pena, Univ. Carlos III de Madrid (Spain)

A localized surface plasmon resonance based fiber optic sensor for temperature sensing has been analyzed theoretically. The effects of the size of the spherical metal nanoparticle on the performance of the sensor have been studied in detail. The high sensitivity of localized surface plasmon resonances to refraction index changes, in collaboration with the high thermo-optic coefficients of Liquid Crystal materials, has result in a fiber optical sensor with high temperature sensitivity. This sensitivity has been demonstrated to be dependent on nanoparticle size. Maximum sensitivities of 4nm/ºC can be obtained for some specific temperature ranges. The proposed sensor will be low cost, and will have all the typical advantages of fiber optic sensors. P103/Paper 9157-602

Optical fiber elements for addressing individual cores in multicore optical fiber sensors

Marek Napierala, InPhoTech Ltd. (Poland), Military Univ. of Technology (Poland); Michal Murawski, Michal Szymanski, Lukasz Ostrowski, Military Univ. of Technology (Poland), InPhoTech Ltd. (Poland); Lukasz Szostkiewicz, InPhoTech Ltd. (Poland); Pawel Mergo, Univ. of Maria Curie-Sklodowska (Poland); Leszek R. Jaroszewicz, Military Univ. of Technology (Poland); Tomasz Nasiłowski, InPhoTech Ltd. (Poland), Military Univ. of Technology (Poland)

Multicore optical fibers gained a lot of interest in the different fields of fiber sensing. This is mainly due to the possibility of carrying out simultaneous measurements on each core and simplicity of such fiber fabrication. A disadvantage of multicore fibers is related to the complex introducing and detecting light from the individual cores. In this paper we discuss two classes of multicore fiber sensors and optical fiber elements for addressing individual cores in this kind of fibers.

P104/Paper 9157-628

Evaluation of a 1540 nm VCSEL for Fibre Bragg Gratings interrogation in dynamic measurement applications Jose A. Garcia-Souto, Pedro Martin-Mateos, Julio Posada-Roman, Pablo Acedo, Univ. Carlos III de Madrid (Spain); David A. Jackson, Univ. Carlos III de Madrid (Spain), Univ. of Kent (United Kingdom)

The performance of a 1540 nm pigtailed VCSEL has been characterized in terms of output power, frequency range and rate of wavelength sweeping for its application in fibre Bragg grating interrogation. Results are presented for the laser operating under optimized control when used to illuminate a single FBG mounted under tension between a fixed plane and a loud speaker cone subject to a range of frequencies at arbitraryplitudes and transients. The ultimate objective is to extend the set-up to a parallel fibre topology supporting 8 FBGs with equal wavelengths.

P105/Paper 9157-634

Remote sensing with nonlinear negative-index metamaterials Alexander K. Popov, Univ. of Wisconsin-Stevens Point (United States), Purdue Univ. (United States); Sergey A. Myslivets, L.V. Kirensky Institute of Physics (Russian Federation)

A concept of the remotely actuated and interrogated four-wave mixing photonic sensor, which employs the negative-index photonic materials, is described. Unique electromagnetic properties of such a metamaterial enable enhancement of frequency conversion and redirection of the signals which carry important information for environmental probing. Four-wave mixing process allows for independent engineering of resonantly enhanced optical nonlinearities and negative refractive index.

P106/Paper 9157-650

Analysis of a fibre-optic sensor design based on SPR in nanowire metamaterial films Ivo T. Leite, INESC TEC (Portugal); Pedro Fernandes, Univ. do Porto (Portugal); Aurelio Hierro-Rodriguez, INESC TEC (Portugal), IFIMUP and IN (Portugal); José Miguel Teixeira, Univ. do Porto (Portugal); Pedro Jorge, INESC TEC (Portugal); Ariel Guerreiro, INESC TEC (Portugal), Univ. do Porto (Portugal)

This paper investigates numerically the performance of a design for an optical sensor of the refractive index of gases and liquids based on smart or functional metamaterial films (smart optical metamembranes).

P107/Paper 9157-657

Analysis of the spectrum distortions of optical fiber Bragg gratings fabricated in-line on a draw tower by the phase mask technique Yu Zheng, Haihu Yu, Huiyong Guo, Xiaofu Li, Desheng Jiang, Wuhan Univ. of Technology (China)

Optical fiber Bragg grating (FBG) arrays can be fabricated in-line on a draw tower using the phase mask technique. On the FBG arrays, some grating spectrum distortions, for example, asymmetric side lobes or deformed side lobes, low extinction ratio of the main reflection peak and comb filter-type peaks, can be observed. We collected different distorted reflectance spectra of the in-line fabricated FBGs and compared them with the simulated spectra of FBGs. By comparing the experimental and theoretical FBG spectra, it is found that the different kinds of spectral distortions are caused by phase shifting, asymmetric apodization and nonlinear chirp. P108/Paper 9157-208

Generation of fiber-based plasmonic airy beam Chunying Guan, Harbin Engineering Univ. (China); Ming Ding, Jinhui Shi, Univ. of Southampton (United Kingdom); Pengfei Wang, Harbin Engineering Univ. (China), Dublin Institute of Technology (Ireland); Ping Hua, Siemens Medical Solutions USA, Inc. (United States); Gilberto Brambilla, Univ. of Southampton (United Kingdom); Libo Yuan, Harbin Engineering Univ. (China)

Compact all-fiber plasmonic Airy-like beam generator is demonstrated. A single slit and a 1D groove array were fabricated by focused ion beam (FIB) milling on the end facet of a single mode optical fiber. The single slit excites the surface plasmonic polaritons (SPPs), which are decoupled into free space by the groove array. The phase of decoupling SPPs is adjusted by the grooves position. Experimental generation of the single Airy-like beam has good consistency with theoretical predictions. The transverse acceleration and nondiffraction properties are observed. The presented plasmonic Airy-like beam generator is of importance to realize all-fiber optical trapping, beam shaping, and fiber integrated devices.

P109/Paper 9157-614

Design of long period fiber grating with optimal sensitivity for detecting adhesion of nano-layer on the fiber surface Palas Biswas, Tanoy K. Dey, Nandini Basumallick, Prasanta K. Sinha, Kamal Dasgupta, Somnath Bandyopadhyay, Central Glass and Ceramic Research Institute (India)

For detecting bio-molecular interaction using long period grating (LPG) we believe that a quantitative data concerning sensitivity for addition of layers on the surface and subsequently to optimize the same appears to be more usefull than defining LPG sensitivity for a surrounding refractive index change in bulk form. For the first time, to the best of our knowledge, we quantify the shift of resonant wavelength (Δλres) of the mode of interest around the transition point as a function of unit bi-layer thickness (Δd) of poly-electrolyte, deposited by ionic self assembly, and subsequently optimize the sensitivity Δλres/Δd. Experimental result show that a shift of ~12.5 nm/bi-layer is possible with optimum number of bi-layer deposition.

P110/Paper 9157-125

Hydrostatic pressure sensitivity of standard polymer fibre Bragg gratings and etched polymer fibre Bragg gratings Kishore Bhowmik, Univ. of New South Wales (Australia), NICTA (Australia); Ginu Rajan, Univ. of New South Wales (Australia); Eliathambybikairajah, Univ. of New South Wales (Australia), NICTA (Australia); Gang D. Peng, Univ. of New South Wales (Australia)

The hydrostatic pressure sensitivity of polymer optical fibre Bragg grating of different diameters is investigated. For this purpose Bragg gratings are inscribed in single-mode polymer fibre and also in etched single-mode polymer fibre. The inherent pressure sensitivity of the grating are experimentally investigated up-to 1MPa by monitoring the change in the reflected peak wavelengths due to pressure. It is observed that polymer FBGs exhibit a positive Bragg wavelength shift and is also more sensitive compared to silica FBGs. The pressure sensitivity of the polymer FBG can be increased by reducing the diameter of the fibre. P111/Paper 9157-533

Sensitive surface plasmon resonance biosensor enhanced by photonic-crystal metallic structure Yunhan Luo, Zhe Chen, Jinan Univ. (China)

In this paper, we propose and analytically demonstrate a novel photonic crystal metallic structure, where a photonic crystal (PC) structure is integrated in a total-internal-reflection (TIR) geometry. This unique configuration introduces a new plasmon excitation mechanism, and the excited plasmon modes satisfy the conditions for both resonance modes in PC structure and Plasmon modes in the metallic structure, which makes it possesses a narrow resonance width, smaller minimum reflectance and higher sensitivity comparing with the conventional SPR sensor. The novel and sensitive PC-metallic biosensor will serve as a promising candidate for optical biosensing, and in enhanced total-internal-reflection fluorescence microscopy. P112/Paper 9157-538

Violet laser power sensor based on micro-fiber coated with methyl blue-functionalized reduced graphene oxide Zhengwen Tian, Jun Zhang, Bing Yang, Jianhui Yu, Zhe Chen, Jieyuan Tang, Yunhan Luo, Xiang Cai, Shaozao Tan, Huihui Lu, Jinan Univ. (China)

A novel all fiber-optic power sensor of violet laser based on methyl blue-functionalized reduced graphene oxide (MB-rGO) film coated on a microfiber (MF) was proposed. The experiments show that when the violet laser illuminating onto the MB-rGO film with power variation from 0.03mw to 12.8mw, the transmitted optical power of the MF changes with a relative variation of ~2.7dB. The novel power sensor of violet laser possesses a sensitivity of ~0.22dB/mw in 1550nm. Furthermore, the MB-rGO-based all fiber-optic violet power sensor is easy to fabricate, compatible with fiber-optic systems and possesses high potentiality in photonics applications such as all fiber-optic broadband sensors, switches and modulators.

Wednesday 4 June

Plenary Presentation II Wednesday 4 June 2014 8:30 AM - 9:30 AM Chair: Manuel López-Amo, Univ. Pública de Navarra (Spain)

8:30: Novel light-based technologies for biomedical applications, (invited) Seok Hyun Yun, Harvard Medical School and Massachusetts Institute of Technology (United States)

Upon absorption of a photon, molecules can be excited or altered, triggering various photochemical events useful for sensing and therapy. The light-induced processes are thermodynamically robust because of high activation energy, and are energy-efficient because downstream biochemical events may amplify their biological effects. Numerous techniques based on photochemical processes have been developed, such as photodynamic therapy and optogenetics. Despite the great promise of the light-based techniques in medicine, a major common challenge has been the difficulty of delivering light deep into the tissue. Owing to intrinsic absorption and scattering, the penetration depth of light is no more than several mm’s in tissue. To date, the clinical use of optical techniques has been limited to superficial layers, such as the skin and retina, or the epithelial surfaces of organs that are accessible by catheters or endoscopes. In this talk, I will present some of the novel, nonconventional, intriguing approaches that have a potential to solve the problem of light delivery, using the concepts originally developed in optical fiber sensor community and employing polymers and cells as biocompatible photonic materials.

Session 4: Chemical, Environmental, Biological, Medical Sensors and Biophotonics I Wednesday 4 June 2014 9:30 AM - 10:30 AM

Session Chairs: Robert A. Lieberman, Intelligent Optical Systems, Inc. (United States) David Jackson; University of Kent, (UK)

Time: 9:30 - 9:45; Paper 9157-212

Exploring the dark continent with fibre Bragg gratings John W. Arkwright, David H. C. Wang, Simon A. Maunder, Neil G. Blenman, CSIRO (Australia); Ian D. Underhill, Griffith Univ. (Australia); Vicki Patton, St. George Hospital (Australia); Phil G. Dinning, Flinders Univ. (Australia)

The lower gastrointestinal tract has been referred to as the ‘Dark Continent’ of the human body because it is so hard to access without resorting to a surgeon’s blade. In response to an unmet clinical need we have developed a fibre optic manometry catheter that is now in clinical use across Australia and New Zealand. The unparalleled detail of colonic activity that these devices provide is being hailed as ground breaking by global experts. In this paper we present the design and clinical application of the catheters, and also some of the (sometimes surprising) requirements of our clinical colleagues. Time: 9:45 - 10:00; Paper 9157-278

Microfluidic device integrated with FBG in Co2+-doped fiber to measure flow rate with nL/s sensitivity Zhengyong Liu, A. Ping Zhang, Hwa-yaw Tam, The Hong Kong Polytechnic Univ. (Hong Kong, China)

Microfluidic device with integrated flow rate sensor is demonstrated. Two glass capillaries and a short length of high light-absorption, Co2+-doped fiber were stacked inside another capillary and drawn into a taper, containing two ~40µm diameter microchannels. An FBG was inscribed in the Co2+-doped fiber. 1480 nm light was used to heat the Co2+-doped fiber and its temperature was measured using an FBG-interrogator operating around 1550nm. The flow rate of the liquid inside in the microchannel can be determined by the temperature and cooling rate of the microchannel. Sensitivity of 0.304nm/(μL/s) and minimum detectable flow rate ~16nL/s were demonstrated.

Time: 10:00 - 10:15; Paper 9157-286

Celiac disease biodetection using lossy mode resonances generated in tapered single-mode optical fibers Abian B. Socorro, Jesus M. Corres, Ignacio Del Villar, Ignacio R. Matias, Francisco J. Arregui, Univ. Pública de Navarra (Spain)

This work presents the development and test of an anti-gliadin antibodies biosensor based on lossy mode resonances (LMRs) to detect celiac disease. Several polyelectrolites were used to perform layer-by-layer assembly processes in order to generate the LMR and to fabricate a gliadin-embedded thin-film. The LMR shifted 20 nm when immersed in a 5 ppm anti-gliadin antibodies-PBS solution, what makes this bioprobe suitable for detecting celiac disease. This is the first time, to our knowledge, that LMRs are used to detect celiac disease and these results suppose promising prospects on the use of such phenomena as biological detectors. Time: 10:15 - 10:30; Paper 9157-356

Fiber optical beam shaping using polymeric structures Ana Rita S. Rodrigues Ribeiro, INESC TEC (Portugal), Univ. do Porto (Portugal); Raquel Queirós, INESC TEC (Portugal); Ariel Guerreiro, INESC TEC (Portugal), Univ. do Porto (Portugal); Carole Ecoffet, Olivier Soppera, Institut de Sciences des Matériaux de Mulhouse (France); Pedro A. S. Jorge, INESC TEC (Portugal)

A method to control the output intensity profile of optical fibers is presented. Using guided wave photo-polymerization in multimode structures the fabrication with modal assisted shaping of polymeric micro lenses is demonstrated. Results showing that a given linear polarized mode can be selectively excited controlling the intensity distribution at the fiber tip are presented. This pattern is then reproduced in the polymeric micro structure fabricated at the fiber tip thus modulating its output intensity distribution. Such structures can therefore be used to obtain at the fiber tip predetermined intensity patterns for attaining optical trapping or patterned illumination.

Coffee Break 10:30 AM - 11:00 AM

Session 5: Chemical, Environmental, Biological, Medical Sensors and Biophotonics II Wednesday 4 June 2014 11:00 AM - 12:30 PM

Session Chair: Brian Culshaw, Strachide Univ. (United Kinddom); Young-Geun Han, Hanyang Univ. (Korea, Republic of) Time: 11:00 - 11:30; Invited Paper 9157-676

Wide and fast wavelength-swept fiber lasers based on dispersion tuning for real-time OCT Shinji Yamashita, The Univ. of Tokyo (Japan)

We recently proposed new wavelength-swept lasers for swept-source OCT (SS-OCT). It is based on a principle called “dispersion tuning”. Since no filters are required, we could achieve the very high sweep rate >500kHz. In this talk, we describe the principle of the dispersion-tuned swept lasers in detail and present our works on the application to the SS-OCT system.

Time: 11:30 - 11:45; Paper 9157-506

High-sensitivity humidity sensors based on TiO2-coated long period fiber grating for high-energy physics applications Gaia Maria Berruti, Marco Consales, Univ. degli Studi del Sannio (Italy); Anna Borriello, CNR, Institute of Molecular and Cell Biology (Italy); Salvatore Buontempo, INFN (Italy); Giovanni Breglio, Univ. degli Studi di Napoli Federico II (Italy); Alajos Makovec, Univ. of Debrecen (Hungary); Paolo Petagna, CERN (Switzerland); Andrea Cusano, Univ. degli Studi del Sannio (Italy)

This contribution deals with a feasibility analysis for the development of fiber optic humidity sensors to be applied in high-energy physics (HEP) experiments currently running at the European Organization for Nuclear Research (CERN). In particular, due to the wide investigations carried out in the last years aimed to assess the radiation hardness capability of fiber optic technology in HEP environments, our multidisciplinary research group has been recently engaged in the development of high-sensitivity TiO2-coated Long Period Fiber Gratings (LPGs) sensors for relative humidity (RH) monitoring at temperatures below 0°C as well as in presence of strong ionizing radiations.

Time: 11:45 - 12:00; Paper 9157-527

Photochemistry on soft-glass hollow-core photonic crystal fibre Ana M. Cubillas, Max Planck Institute for the Science of Light (Germany), Excellence Cluster “Engineering of Advanced Materials" (Germany); Xin Jiang, Tijmen G. Euser, Max Planck Institute for the Science of Light (Germany); Nicola Taccardi, Excellence Cluster Engineering of Advanced Materials (Germany), Lehrstuhl für Chemische Reaktionstechnik (Germany); Philip S. Russell, Max Planck Institute for the Science of Light (Germany), Excellence Cluster “Engineering of Advanced Materials (Germany), Univ. Erlangen-Nürnberg (Germany)

Hollow-core photonic crystal fibre (HC-PCF) offers strong light confinement and long interaction lengths in an optofluidic channel. These unique advantages have motivated its recent use as a highly efficient and versatile microreactor for liquid-phase photochemistry and catalysis. In this work, we use a soft-glass HC-PCF to carry out photochemical experiments in a high-index solvent such as toluene. The high-intensity and strong confinement in the fibre is demonstrated to enhance the performance of a proof-of-principle photolysis reaction.

Time: 12:00 - 12:15; Paper 9157-576 Fiber optic sensing system for monitoring of coal waste piles in combustion Duarte Viveiros, INESC Porto (Portugal); Joana Ribeiro, Univ. do Porto (Portugal); J. P. Carvalho, João Ferreira, INESC Porto (Portugal); Ana Pinto, Rosa Perez-Herrera, Silvia Diaz, Univ. Pública de Navarra (Spain); Alexia Lopez-Gil, Alejandro Dominguez-Lopez, Oscar Esteban, Hugo F. Martins, Sónia Martin-Lopez, Univ. de Alcalá (Spain); Hardy Baierl, Jean-Louis Auguste, Raphael Jamier, Sébastien Rougier, CNRS, XLIM Institut de Recherche (France); José Luís C. Santos, INESC Porto (Portugal), Univ. do Porto (Portugal); Deolinda Flores, Univ. do Porto (Portugal); P. Roy, CNRS, XLIM Institut de Recherche (France); Miguel G. Herraez, Univ. de Alcalá (Spain); Manuel Lopez-Amo, Univ. Pública de Navarra (Spain); José M. Baptista, INESC Porto (Portugal), Univ. da Madeira (Portugal)

The combustion of coal wastes resulting from mining is of particular environmental concern and therefore the importance of the proper management involving real-time assessment of their status and identification of probable evolution scenarios is recognized. Continuous monitoring of combustion temperature and emission levels of certain gases opens the possibility to plan corrective actions to minimize their negative impact in the surroundings. Optical fiber technology is well-suited to this purpose and in this work

it is described the main attributes of a fiber optic sensing system projected to gather data on distributed temperature and gas emission in these harsh environments.

Time: 12:15 - 12:30; Paper 9157-37

High sensitivity methane and ethane detection using low-loss mid-IR hollow-core photonic bandgap fibers Marco N. Petrovich, Alex Heidt, Natalie Wheeler, Naveen K. Baddela, David J. Richardson, Univ. of Southampton (United Kingdom)

We present sub-ppm sensitivity, broadband gas absorption measurements using improved hollow-core photonic-bandgap fibers with low loss in the range 3-3.6um. The sensitivity levels, unprecedented for a fiber-based sensor system, were achieved by addressing the strong mid-IR vibrational bands through use of a high-intensity supercontinuum source and by exploiting long interaction lengths in the HC-PBGF. We measured mixtures of methane (1000ppm) and ethane (50.4ppm) and attained 7 and 0.9ppm sensitivities for 0.925 and 5.69m long HC-PBGF samples, respectively, from high-resolution (0.2nm) spectra. Significant scope for further sensitivity improvement exists through use of longer fibers in combination with more sophisticated sensing schemes.

Lunch Break 12:30 PM - 2:00 PM

Session 6: Distributed Sensing I Wednesday 4 June 2014 2:00 PM - 3:30 PM Session Chairs: Kazuo Hotate, The Univ. of Tokyo (Japan); Xiaoyi Bao, Univ. of Ottawa (Canada)

Time: 14:00 - 14:30; Invited Paper 9157-677

The intelligent distributed acoustic sensing Tom Parker, Silixa, Ltd. (United Kingdom)

Distributed Acoustic Sensing (DAS) technology has progressed rapidly from being capable of event detection only to faithfully capturing the full acoustic signal (amplitude, frequency and phase) at all points along the sensing fibre. In this paper we demonstrate the performance of one such sensor and describe how the unique nature of DAS data enables a range of ground-breaking industrial applications. Time: 14:30 - 14:45; Paper 9157-592

MilliKelvin resolution in cryogenic temperature distributed fibre sensing based on coherent Rayleigh scattering Xin Lu, Marcelo Soto, Luc Thévenaz, Ecole Polytechnique Fédérale de Lausanne (Switzerland)

The response of a distributed temperature sensor based on coherent Rayleigh scattering is experimentally studied in the temperature range from 77 K up to 300 K, using fibres with standard and ORMOCER coating. A precise and absolute frequency scan is performed to obtain the best temperature resolution that turns out to be in the mK range. Experimental results point out that heating and cooling processes, at cryogenic temperatures, exhibit different temperature sensitivities when standard single-mode fibres are used; however, specially coated fibres exhibit better repeatability. Time: 14:45 - 15:00; Paper 9157-404

Distributed measurement of intermodal beat length in an elliptic-core two-mode fiber by Brillouin dynamic grating Yong Hyun Kim, Kwang Yong Song, Chung-Ang Univ. (Korea, Republic of)

Optical time-domain measurement and characterization of intermodal beat length in an elliptic-core two-mode fiber (e-core TMF) is demonstrated using Brillouin dynamic grating. A mode-selective coupler is used for selective launch and retrieval of different modes, and the operations of BDG for four different pairs of pump-probe (LP01x-LP11x, LP01x-LP11y, LP01y-LP11x, LP01y-LP11y) are observed, representing a fine structure of modal birefringence in the e-core TMF. Distributed measurement of the BDG spectrum is performed for each pair of pump-probe with 1.5 m spatial resolution mapping the difference of the effective refractive indexes of spatial and polarization modes along a 75 m TMF.

Time: 15:00 - 15:15; Paper 9157-93

Distributed optical fibre audible frequency sensor Ali Masoudi, Mohammad Belal, Trevor P. Newson, Univ. of Southampton (United Kingdom)

A distributed optical fibre sensor is demonstrated which is capable of quantifying acoustic and dynamic strain disturbances along a 1km sensing fibre. A phase-OTDR technique is used to detect the dynamic perturbations using the phase-difference between the backscattered light from two separate sections of the sensing fibre. The demonstrated sensor detects multiple dynamic perturbations simultaneously within a frequency range of 200Hz to 5000Hz with a frequency resolution of 10Hz and a spatial resolution of 1m. Time: 15:15 - 15:30; Paper 9157-470

Simple method for the elimination of polarization noise in BOTDA using balanced detection of orthogonally polarized Stokes and anti-Stokes probe sidebands Alexia López-Gil, Alejandro Domínguez-López, Sonia Martín-López, Miguel González-Herráez, Univ. de Alcalá (Spain)

Given the strong polarization sensitivity of Stimulated Brillouin Scattering (SBS), in Brillouin Optical Time Domain Analysis (BOTDA) it turns out to be indispensable to perform some kind of polarization scrambling, either in the pump pulse, or the probe signal (or both). This is usually accomplished using polarization scrambling/switching systems, which, being mechanical, tend to be not as robust as it would be desirable. In this paper we propose a completely passive system, with no moving parts, to perform the polarization scrambling in a BOTDA. It is based on the use of balanced detectionong the orthogonally polarized Stokes and anti-Stokes bands of the probe signal. The setup requires no alignment and provides a performance similar to a conventional BOTDA sensor.

Coffee Break 3:30 PM- 4:00 PM

Session 7: Distributed Sensing II Wednesday 4 June 2014 4:00 PM - 5:00 PM

Session Chairs: Yun-Jiang Rao; University of Electronic Science and Technology of China, (China) Gabriele Bolognini, Consiglio Nazionale delle Ricerche (Italy)

Time: 16:00 - 16:30; Invited Paper 9157-678

Distributed strain and temperature sensing based on Brillouin scattering in

plastic optical fibers Yosuke Mizuno, Tokyo Institute of Technology (Japan)

Unlike glass optical fibers, plastic/polymer optical fibers (POFs) are so flexible that they can withstand over 50% strain. In this presentation, we review the fundamental sensing properties of Brillouin scattering in POFs at 1.55 μm, showing its potential applicability to high-precision temperature sensing, cryogenic temperature sensing, and large-strain sensing with novel “memory” function. Time: 16:30 - 16:45; Paper 9157-499

Discriminative and distributed measurement of temperature and strain with time-division pump-probe-read light generation by single laser diode in Simplified BOCDA system Tsuyoshi Matsumoto, Masato Kishi, Kazuo Hotate, The Univ. of Tokyo (Japan)

A simplified BOCDA system for discriminative and distributed measurement of temperature and strain is proposed and demonstrated, in which pump, probe and read light are generated with single laser diode in a time-division way. A linearly-polarized pump and probe light launched in X-polarization axis of a polarization maintaining fiber are used to generate Brillouin dynamic grating, and the orthogonally polarized read light is used to observe Brillouin dynamic grating reflection. We have successfully demonstrated the discriminative and distributed measurement of temperature and strain in the detection along a 70 cm strain applied area.

Time: 16:45 - 17:00; Paper 9157-605

Bragg gratings in carbon coated optical fibers and their potential sensor applications in harsh environment Yaowen Li, David J. Kudelko, Adam S. Hokansson, Debra A. Simoff, Andrei A. Stolov, Joanna Ng, Joel Mann, OFS Specialty Photonics Div. (United States)

We have demonstrated that fiber Bragg gratings can be written through the carbon layer of carbon-coated optical fibers having different coating thicknesses. Specifically, grating index modulationplitudes of ~2.5x10-5 and 0.52x10-5 were obtained in optical fibers having carbon layers 29 nm and 56 nm thick, respectively, without any extra photosensitization of the fibers. Subsequent experimental results showed that the carbon coatings in the grating areas didn’t change their hermetic properties. Finally, we describe the advantages of these gratings and their potential applications in fiber optic sensing.

Poster Session II (109 papers)

Wednesday 4 June 2014 5:00 PM - 6:30 PM Panel or Board number 1 / Paper 9157-7

Anomalous refractive index of ultrathin gold nanoparticle film coated on tilted fiber Bragg grating Wenjun Zhou, David J. Mandia, Matthew B. E. Griffiths, Seán T. Barry, Jacques Albert, Carleton Univ. (Canada)

Effectively size-dependent refractive index of ultrathin gold film deposited by chemical vapour deposition (CVD) is experimentally investigated at infrared wavelength. By coating the gold film on tilted fiber Bragg grating (TFBG), the wavelength andplitude of the TFBG cladding modes are modulated by the interaction between their evanescent fields and the gold film. Then, the complex refractive index of the gold film in in-plane and out-of-plane directions can be calculated from the effective indices of the cladding modes with azimuthally and radically polarized electric fields at cladding boundary, respectively. The obtained real parts of the complex refractive indices are about 10 times higher than that of bulk gold, for the gold films with thickness from 6 to 65 nm, while the imaginary parts are 2 orders of magnitude lower than the bulk value in the both of directions. P2/Paper 9157-41

Ex vivo determination of chewing patterns using FBG and artificial neural networks Leandro Z. Karam, Vinicius Pegorini, Univ. Tecnológica Federal do Paraná (Brazil); Christiano Santos Rocha Pitta, Federal Institute of Paraná (Brazil); Tangriani Simioni Assmann, Rafael Cardoso, Hypolito J. Kalinowski, Jean Carlos Cardozo da Silva, Univ. Tecnológica Federal do Paraná (Brazil)

This paper reports the experimental procedures performed in a bovine head for the determination of chewing patterns during the mastication process. FBG were fixed in the jaw to monitor the biomechanical forces involved in the chewing process. The acquired signals from the sensors fed the input of an artificial neural network aiming at the classification of the measured chewing patterns for each material used in the experiment. The results obtained from the simulation of the chewing process presented different patterns for the different textures of plasticine, resulting on the determination of three chewing patterns with a classification error of 5%.

P3/Paper 9157-45

Fiber-optic dual EFPI/FBG for radiofrequency ablation monitoring in liver: ex-vivo experiments Daniele Tosi, Univ. of Limerick (Ireland); Edoardo Gino Macchi, Giovanni Braschi, Mario Gallati, Univ. degli Studi di Pavia (Italy); Alfredo Cigada, Politecnico di Milano (Italy); Sandro Rossi, IRCCS Policninico San Matteo Foundation (Italy); Sven Poeggel, Gabriel Leen, Elfed Lewis, Univ. of Limerick (Ireland)

We present a miniature and biocompatible fiber-optic sensing system, for specific application in monitoring of the radiofrequency thermal ablation (RFA) process. The sensing system is based on combination of Extrinsic Fabry-Perot Interferometry (EFPI) sensor for pressure detection, and Fiber Bragg Grating (FBG) for temperature measurement. The dual pressure/temperature measurement shows an extremely low cross-sensitivity. Measurements have been performed ex-vivo on porcine liver, recording several RFA procedures in different location. Maximum values of 164°C and 162 kPa have been recorded on the ablation point. P4/Paper 9157-67

Fiber-optic extrinsic Fabry-Perot interferometry pressure sensors for in-vivo urodynamic analysis Sven Poeggel, Daniele Tosi, Univ. of Limerick (Ireland); Ferdinando Fusco, Vincenzo Mirone, Simone Sannino, Laura Lupoli, Juliet Ippolito, Univ. degli Studi di Napoli Federico II (Italy); Gabriel Leen, Elfed Lewis, Univ. of Limerick (Ireland)

We report a fiber-optic sensing system based on Extrinsic Fabry-Perot Interferometry (EFPI), for pressure detection in medical applications. The system allows dual channel detection, with probes having typical sensitivity of 1.3 nm/kPa and accuracy of 0.6 cmH2O, diameter of 0.2 mm, and perfect biocompatibility. Pressure probes have been applied to urodynamic analysis, measuring both bladder and abdominal pressure. Measurements have been carried out in-vivo on seven patients having different bladder conditions. The fiber-optic probes have been compared with a PICO2000 urodynamic instrument, showing improved accuracy, a good reproduction of bladder-related events, and increased responsivity to local pressure variations.

P5/Paper 9157-69

Biofuncationalized microfiber Bragg grating for acid-based sensing Yang Ran, Yunyun Huang, Xiang Shen, Dandan Sun, Xiuxin Wang, Long Jin, Jie Li, Baiou Guan, Jinan Univ. (China)

We demonstrate an acid-based sensor from the biofuncationalized microfiber Bragg grating. By electrostatic self-assembly layer-by-layer technique, the film consisting of sodium alginate which has hygroscopic response to the potential of hydrogen is coated on the fiber surface. Consequently, the refractive index variation of the sensing film caused by water absorption can be measured by mFBG’s higher order mode peak which can be translated into pH value information. The sensitivity of the sensor is received as high as 265pm/pH. P6/Paper 9157-76

Optimization and characterization of femtosecond laser inscribed in-fiber microchannels for liquid sensing Graham C. B. Lee, Chengbo Mou, Kaiming Zhou, Kate Sugden, Aston Univ. (United Kingdom)

In-fiber microchannels were fabricated directly in standard single mode fiber using the femtosecond laser inscribe and etch technique. This method of creating in-fiber microchannels offers great versatility since it allows complex three dimensional structures to be inscribed and then etched with hydrofluoric acid. Four in-fiber microchannel designs were experimentally investigated using this technique. Device characteristics were evaluated through monitoring the spectral change while inserting index matching oils into each microchannel - a R.I. sensitivity up to 1.55 dB/RIU was achieved. Furthermore, a simple Fabry-Pérot based refractometer with a R.I. sensitivity of 2.75 nm/RIU was also demonstrated.

P7/Paper 9157-77

A novel liquid viscosity measuring approach based on optical trapping technology Yu Zhang, Liang Peibo, Liu Zhihai, Lei Jiaojie, Zhao Enming, Yang Jun, Yuan Libo, Harbin Engineering Univ. (China)

We present a novel liquid viscosity measuring approach based on the optical trapping technology. We put a “test-micro-particle” enclosed in a confined space built by a quartz capillary tube and two opposite-inserted optical fibers to construct the test cell. In order to make the test cell have the ability of auto-ready and easy-reset, we design and fabricate a special notch-shape in the ends of two fibers. This novel approach provides a new probably development direction for the optical tweezers technology applying on the sensing and measuring fields, and solve the optical tweezers measurement repeatability problems. P8/Paper 9157-85

Comparison of the fiber-optic dosimeter and semiconductor dosimeter for use in diagnostic radiology Wook Jae Yoo, Sang Hun Shin, Hyeok In Sim, Seunghan Hong, Seon Geun Kim, Jae Seok Jang, Jae Seok Kim, Hye Su Jeon, Gu Won Kwon, Kyoung Won Jang, Konkuk Univ. (Korea, Republic of); Seunghyun Cho, Soongsil Univ. (Korea, Republic of); Bongsoo Lee, Konkuk Univ. (Korea, Republic of)

A fiber-optic dosimeter (FOD) was fabricated using a plstic scintillating fiber, a plastic optical fiber, and a multi-pixel photon counter to measure entrance surface dose (ESD) in diagnostic radiology. Under changing tube current and irradition time of the digital radiography (DR) system, we measured the scintillating light and the ESD simultaneously. As experiemtnal results, the total counts of the FOD were changed in a manner similar to the ESDs of the semiconductor dosimeter (SCD). In conclusion, we demonstrated that the proposed FOD minimally affected the diagnostic information of DR image while the SCD caused serious image artifacts. P9/Paper 9157-86

Polarimetric fiber grating biosensor for in-situ high-sensitive intracellular density measurement Tuan Guo, Fu Liu, Yu Liu, Jinan Univ. (China); Nan-Kuang Chen, National United Univ. (Taiwan); Bai-Ou Guan, Jinan Univ. (China); Jacques Albert, Carleton Univ. (Canada)

High sensitivity biological sample measurements have been achieved by using a 12o tilted fiber Bragg grating (TFBG). Human acute leukemia cells with different intracellular densities and refractive index (RI) ranging from 1.3342 to 1.3344 were clearly discriminated in-situ by using the differential transmission spectrum between two orthogonal polarizations for the last guided mode resonance before “cut-off”, with anplitude variation sensitivity of 1.8×104 dB/RIU and a limit of detection of 2×10-5 RIU. The technique is inherently temperature-insensitive. P10/Paper 9157-97

Highly sensitive gas sensor based on graphene/microfiber hybrid waveguide with Mach-Zehnder interferometer Yu Wu, Baicheng Yao, Yang Cheng, Anqi Zhang, Yuan Gong, Yunjiang Rao, Univ. of Electronic Science and Technology of China (China)

A high sensitivity NH3 gas sensor based on graphene/microfiber hybrid waveguide (GMHW) is reported for the first time. Enhanced by the graphene, a very high sensitivity of 0.3ppm is achieved for GMHW-based NH3 gas sensing. This work may open a window for development of novel GMHW-based gas sensors with high sensitivity, small footprint, easy fabrication and low cost.

P11/Paper 9157-98

Graphene-coated microfiber FBG for highly sensitive gas sensing Bai-Cheng Yao, Yu Wu, Univ. of Electronic Science and Technology of China (China); Anqi Zhang, Johns Hopkins Univ. (United States); Cai-bin Yu, Yuan Gong, Yunjiang Rao, Univ. of Electronic Science and Technology of China (China)

In this paper, a novel graphene-coated microfiber Bragg grating (GMFBG) sensor is proposed and demonstrated for detection of gas concentration, for the first time. Taking advantage of the surface field enhancement and polar molecular adsorption by the graphene film, we find that this structure is very sensitive to local chemical gas concentration, and the obtained sensitivities are 0.2 and 0.5ppm for NH3 and Xylene gas for tiny gas variation, respectively. Such a miniature GMFBG sensor could find applications in biological or chemical sensing, such as for trace analysis. P12/Paper 9157-104

Dual-parameter monitoring based on fiber loop mirror assisted reflective long period fiber grating

Jianying Yuan, Chun-Liu Zhao, GuiLan Feng, Juan Kang, Shangzhong Jin, China Jiliang Univ. (China)

In this paper, a dual-parameter measurement scheme based on a fiber loop mirror (FLM) assisted reflective long period fiber grating (LPFG) is proposed and experimentally demonstrated. Due to the Sagnac fiber loop mirror, a reflective long period fiber grating was generated resulting in a compact sensing routing design. Moreover, the refractive index and temperature could be simultaneously determined through monitoring two dips’ wavelength shifts of the FLM assisted reflective LPFG. Experimental results show that the RI sensitivity of the sensor is from 34.48nm/RIU to 241.12nm/RIU in the RI range from 1.3467 to 1.4526, and the temperature sensitivity can reach 1.5274nm/℃.

P13/Paper 9157-107

Fabrication of a photocurable highly sensitive opticalmonia sensor for aquaculture application Aiman S. Abd Aziz, Noor H. Ismail, Mohd N. Mohd Zain, Gunawan Witjaksono, MIMOS BERHAD (Malaysia)

A simple sensor fabrication process formonia fluorescence based optical sensing has been developed by immobilizing fluorescence dyes in a UV-photocurable acrylate host polymer matrix. The acrylate based host matrix offers rapid curing, ease of preparation, excellent dyes entrapment and self-adhesive properties. The non-plasticized acrylate matrix containingmonia sensitive components have demonstrated excellent sensitivity towards dissolvedmonia down to part-per-billion (ppb) detection level. The simple single step fabrication ofmonia fluorescence based optical sensor offers great manufacturing capability for aquaculture quality monitoring.

P14/Paper 9157-123

Discrimination of chemical vapor and temperature using an in-line modal interferometer based on an exterior hole-assisted polarization-maintaining photonic crystal fiber Min-Seok Yoon, Naram Jun, Hanyang Univ. (Korea, Republic of); Sang Bae Lee, Korea Institute of Science and Technology (Korea, Republic of); Young-Geun Han, Hanyang Univ. (Korea, Republic of)

A reflective in-line modal interferometer based on a polarization-maintaining photonic crystal fiber (PM-PCF) with two exterior air holes is proposed for simultaneous measurement of chemical vapor and temperature. After fusion-splicing the PM-PCF with a standard single-mode fiber, we collapse all of air holes in the PM-PCF resulting in two types of interference patterns between the core and the cladding modes in the PM-PCF depending on two polarization states. Different sensitivities corresponding to input polarization states are utilized for discrimination between chemical vapor and temperature sensitivities. P15/Paper 9157-124

Simultaneous measurement of radiation dose and strain based on an erbium-doped fiber ring laser incorporating a fiber Bragg grating Young Bo Shim, Hanyang Univ. (Korea, Republic of); Younghoon Ji, Korea Institute of Radiological and Medical Sciences (Korea, Republic of); Young-Geun Han, Hanyang Univ. (Korea, Republic of)

We propose a sensing scheme of an erbium-doped fiber (EDF) ring laser for multi-monitoring of radiation dose and strain simultaneously. The EDF and fiber Bragg grating (FBG) are exploited as sensing probes for simultaneous measurement of radiation dose and strain. The output power and the lasing wavelength of the proposed EDF laser are changed by increasing the radiation dose and strain, respectively. The radiation and strain sensitivities were measured to be 8.4 dB/km∙Gy and 0.81 pm/ue, respectively.

P16/Paper 9157-131

Adiabatic tapered optical fiber fabrication for exciting whispering gallery modes in microcavities Zeinab Chenari, Hamid Latifi, Rahele hashemi, Fateme Doroudmand, Shahid Beheshti Univ. (Iran, Islamic Republic of)

The adiabatic biconical fiber taper (ABFT)/microresonator photonic devices have been widely suggested and demonstrated for sensing of physical, chemical, and biological properties of the environment situated near or at the microresonator surface. This article demonstrates an investigation and analysis of a tapered fiber fabrication using an etchant droplet method. To achieve precise control on process, a two-step etching method is proposed (using 48% concentration of HF acid and Buffered HF) which results in low-loss adiabatic tapered fiber. A spectrum analysis monitoring in addition to a microscopy system was used to verify the etching progress. Tapers with losses less than 0.4 dB in air and 4.5 dB in water are demonstrated. A biconical fiber taper fabricated using this method was used to excite the WGMs on a microsphere surface in aquatic environment. P17/Paper 9157-133

Tapered optical fibre sensor for detection of hydrocarbon spills in seawater José Antonio Sánchez Martín, Eusebio Bernabeu Martínez, Ana Rodríguez Aramendía, Anahí Villalba Pradas, Univ. Complutense de Madrid (Spain); Estrella Cruzado Rodríguez, Miguel Pardo de Santayana Carrillo, CEPSA (Spain)

Three devices based on tapered optical fibres are used to determine the presence of pollutants in water, through the measure of their spectral transmittance. Tapered optical silica fibers, coated (or not) with metallic and dielectric layers (Al or Cu and TiO2) are employed. It is found that, with our experimental arrangement, the presence of products derived from gasoline spills can be determined when we use the coated tapers. A complete characterization of the three different tapers is made in a wide spectral range (1300-1650 nm) and the wavelengths most suitable to detect and discern the hydrocarbons measured are identified. The results obtained show that these devices can be used for the early detection of oil spills in seawater in an industrial environment as simple and versatile sensors that can be self-cleaned with the movement of seawater.

P18/Paper 9157-163

Ultra-highly sensitive hydrogen sensor based on fiber Fabry-Perot interferometer with Pt/WO3 coating Yao Wang, Minghong Yang, Guilin Zhang, Jixiang Dai, Wuhan Univ. of Technology (China); Yi Zhang, Zhi Zhuang, Institute of Structural Mechanics (China)

A miniaturized fiber tip Fabry-Perot interferometer (FPI) with Pt/WO3 coating was demonstrated as a hydrogen sensor. The air-cavity of FPI was formed by inserting a single mode fiber (SMF) into a partially polymer-filled glass capillary, which was highly sensitive to temperature. A layer of Pt/WO3 was coated on the glass capillary of the FPI serving as a reaction heater upon hydrogen exposure. The heat locally raised the FPI temperature, which led to the wavelength shift of interference spectrum. The average wavelength shift of two interference dips was -20.3 nm upon exposure to ~20000 ppm hydrogen concentration. The hydrogen sensitivity of the sensor was estimated to be better than 1 pm/ppm. P19/Paper 9157-179

Eccentric core optical fiber for distributed sensing Jianxia Liu, Libo Yuan, Harbin Engineering Univ. (China)

An eccentric core optical fiber (ECOF) for distributed evanescent field sensing is proposed. The finite element method (FEM) is utilized to analyze characteristics of the ECOF, including the fractional power of coating and core. A strong evanescent field exits in the coating of the ECOF due to a small distance between the core and the coating. The sensitivity or resolution of this kind sensing fiber is analyzed. The sensitivity is ~0.25dB/RIU or resolution of in the range of 1.4-1.42. The sensing length is in the range of 16m-160m. P20/Paper 9157-182

A temperature compensated optical fibre bending sensor for physiological measurement Mohd Anwar Zawawi, Univ. of Limerick (Ireland), Univ. Malaysia Pahang (Malaysia); Sinead O'Keeffe, Elfed Lewis, Univ. of Limerick (Ireland)

The light attenuation measurement of a plastic optical fibre sensor based on a referenced intensity modulation technique with respect to different input voltage level and room temperature has been investigated. The results show that light attenuation at the sensor output and reference output are dependent on the source (LED) drive current and temperature, but the output ratio is small and tolerable for this application. This is significant for bending monitoring applications using optical fibre sensor based on intensity modulation, providing a more reliable technique based on power and temperature compensation.

P21/Paper 9157-184

Real-time monitoring of intracellular signal transduction in PC12 cells by non-adiabatic tapered optical fiber biosensor Mohammad Ismail Zibaii, Hamid Latifi,ir Asadollahi, Zahra Noraeepoor, Leila Dargahi, Shahid Beheshti Univ. (Iran, Islamic Republic of)

Real-time observation of intracellular process of signal transduction is very useful for biomedical and pharmaceutical applications as well as for basic research work of cell biology. For feasible and reagentless observation of intracellular alterations in real time, we examined the use of a nonadiabatic tapered optical fiber (NATOF) biosensor for monitoring of intracellular signal transduction that was mainly translocation of protein kinase C via refractive index change in PC12 cells adhered on tapered fiber sensor without any indicator reagent. PC12 cells were stimulated with KCl. Our results suggest that complex intracellular reactions could be real-time monitored and characterized by NATOF biosensor. P22/Paper 9157-202

Temperature and surrounding refractive index insensitive cascaded long period grating chemical sensor Serhiy Korposh, Stephen W. James, Cranfield Univ. (United Kingdom); Seung-Woo Lee, Kitakyushu Univ. (Japan); Ralph P. Tatam, Cranfield Univ. (United Kingdom)

The response to temperature and refractive index (RI) of cascaded long period gratings operating at or near the phase matching turning point was studied. Temperature- and RI-induced changes of the phase of the channelled spectrum and wavelength shift of the long period grating’s resonance band envelope were observed for two conditions; when the length of fibre separating the long period gratings was perturbed and when the whole length of the device was perturbed. It is shown that when the central section of the device is perturbed the phase of the channelled spectrum changes and the envelope remains fixed, while when the entire device is perturbed the phase and central wavelength of the envelope shift at the same rate. Thus measurement of changes in the channelled spectrum with respect to the centre of the resonance band envelope offers a means for developing sensors whose response is compensated for temperature and RI. P23/Paper 9157-206

Nonadiabatic tapered optical fiber biosensor for detection of potassium ion using DNA aptamer in neural application Mohammad Ismail Zibaii, Hamid Latifi,ir Asadollahi, Shahid Beheshti Univ. (Iran, Islamic Republic of)

A single-mode nonadiabatic tapered optical fiber (NATOF) biosensor based on ssDNA aptamer for detection of potassium ion (K+) was developed. Upon binding to K+, the G-rich single-stranded DNA can fold into the G-quadruplex structure, thus allowing the formation of G-quadruplex complex after incubation with K+ which is led to changing in refractive index (RI). Under optimum conditions, the wavelength shift was proportional to the concentration of K+ in the range of 10 ×10-4 to 2×10-2 mM. A detection limit of 4.5×10-4 was achieved. Moreover, this method was able to detect K+ with high selectivity in the presence of Na+ ion of biological fluids.

P24/Paper 9157-214

Radiation dosimetry with fiber Bragg gratings Saverio Avino, CNR, Istituto Nazionale di Ottica (Italy); Vittoria D'Avino, CNR, Institute of Biostructure and Bioimaging (Italy); Antonio Giorgini, CNR, Istituto Nazionale di Ottica (Italy); Roberto Pacelli, Univ. degli Studi di Napoli Federico II (Italy); Raffaele Liuzzi, Laura Cella, CNR, Institute of Biostructure and Bioimaging (Italy); Gianluca Gagliardi, Paolo De Natale, CNR, Istituto Nazionale di Ottica (Italy)

The measurement and monitoring of radiation dose delivered in patient tissues is a critical aspect in radiation therapy. Various dosimeters have proven effective in measuring radiations at low doses. However, there is a growing demand for new dosimeters based on small, non-invasive and high resolution devices. Here we report on a miniature dosimeter based on an optical fiber cavity. We demonstrate an ultimate detection limit of 160 mGy with an effective interaction region of 6 x 10^(-4) mm^3. Due to its reliability, compactness and biomedical dose level sensitivity, our system shows itself suitable for applications in radiation therapy dosimetry. P25/Paper 9157-226

An ultra-sensitive localised surface plasmon resonance fibre device for environmental sensing based upon a structured bi-metal coating Thomas D. Allsop, Aston Univ. (United Kingdom); Ron Neal, Univ. of Plymouth (United Kingdom); Chengbo Mou, Aston Univ. (United Kingdom); Kyriacos Kalli, Cyprus Univ. of Technology (Cyprus); David J. Webb, Aston Univ. (United Kingdom)

We demonstrate a bi-metal coating (platinum and gold or silver) localised surface plasmon resonance fibre device that produces an index spectral sensitivity of over 11,000 nm/RIU, yielding an index resolution of 5×10-6 in the aqueous index regime, consisting of a structured multi-layered thin film on D-shaped fibre

P26/Paper 9157-229

Cardiac induced localised motion of the human torso detected by a long period grating fibre optic sensing scheme Thomas D. Allsop, Aston Univ. (United Kingdom); Glynn Lloyd, Moog Insensys Ltd. (United Kingdom); Ranjeet Bhamber, Aston Univ. (United Kingdom); Ljupco Hadzievski, Univ. of Belgrade (Serbia); Michael Halliday, Cytec Process Materials (Keighley) Ltd. (United Kingdom); David J. Webb, Aston Univ. (United Kingdom)

Cardiovascular health of the human population is a major concern for medical clinicians, with cardiovascular diseases responsible for 48% of all deaths worldwide, according to the World Health Organisation. Therefore the development of new practicable and economical diagnostic tools to scrutinise the cardiovascular health of humans is a major driver for clinicians. We offer a new technique to obtain seismocardiographic signals covering both ballistocardiography (below 20Hz) and audible heart sounds (20Hz upwards). The detection scheme is based upon an array of curvature/displacement sensors using fibre optic long period gratings interrogated using a variation of the derivative spectroscopy interrogation technique

P27/Paper 9157-233

Bent fused fiber taper intermodal interferometer as a refractive index sensor Tinko A. Eftimov, Plovdiv Univ. (Bulgaria); Wojtek J. Bock, Univ. du Québec en Outaouais (Canada); Emil Penchev, Univ. of Food Technologies (Bulgaria)

In the present paper we study the response to surrounding refractive index (SRI) changes of bent fused fiber tapers. The core-cladding mode interference response occurs at particular bending angles and the refractometric response exhibits different sensitivities. The sensitivities greater than 3000 nm/r.i.u. for SRI (surrounding refractive index) larger than 1.43 and as high as 6000 nm/r.i.u. are reached for SRI above 1.44. P28/Paper 9157-234

Interferometric fiber sensor using exposed core microstructured optical fiber for refractive index based biochemical sensing Linh V. Nguyen, Stephen C. Warren-Smith, Alan Cooper, Tanya M. Monro, The Univ. of Adelaide (Australia)

We proposed and experimentally demonstrated an in-fiber interferometric-type sensor by splicing an exposed core microstructured optical fiber (ECF) with lead-in and lead-out single mode fibers (SMFs) for refractive index-based biochemical sensing applications. Due to the multimode characteristic of the ECF, several modes can be excited at the lead-in splicing point and, after propagating through the ECF section, arrive at the lead-out splicing point with different phases forming a multi-arm interference pattern in the transmission spectrum of the device. Two dominant modes were found be consistently excited by maximizing the butt coupling

between ECF and SMFs. The interference fringes shifts differently upon applying liquids of different refractive index on the exposed side of the ECF.

P29/Paper 9157-255

Controlling cone angle of the tapered tip fiber using dynamic etching Hamed Nikbakht, Hamid Latifi, Taherehini, Zeinab Chenari, Shahid Beheshti Univ. (Iran, Islamic Republic of)

In this paper, a new type of dynamic chemical etching is used to fabricate different fiber tips with different cone angles. It was done by controlling surface level of hydrofluoric acid relative to the fiber, with changing volume of the acid in the container using a syringe pump. Using this method the cone angle of the tip is effectively controlled and angles between 1o and 30o was obtained. P30/Paper 9157-264

Study of deformation of resin cements used in fixing of root posts through fiber Bragg grating sensors C. A. Pulido, State Univ. of Ponta Grossa (Brazil); Ana G. Franco, Leandro Z. Karam, Hypolito J. Kalinowski, Univ. Tecnológica Federal do Paraná (Brazil); O. M. M. Gomes, State Univ. of Ponta Grossa (Brazil)

The aim of the study was to evaluate the polymerization shrinkage “in situ” in resin cements inside the root canal during the fixation of glass fiber posts. For cementation teeth were randomly divided into 2 groups according to the resin cement used: Group1 – resin cement dual Relyx ARC (3M/ESPE), and Group 2 – resin cement dual Relyx U200 (3M/ESPE). Before inserting the resin cement into the root canal, two Bragg grating sensors were recorded and pasted in the region without contact with the canal, one at the apical and other at the coronal thirds of the post. The sensors measured the deformation of the resin cements in coronal and apical root thirds to obtain the values in micro-strain. P31/Paper 9157-265

Sensitive protein detection using an optical fibre long period grating sensor anchored with silica core gold shell nanoparticles Leonel Marques, F.U. Hernandez, Sergiy Korposh, Matt Clark, Stephen Morgan, Univ. of Nottingham (United Kingdom); Stephen W. James, Ralph P. Tatam, Cranfield Univ. (United Kingdom)

An optical fibre long period grating (LPG), modified with a coating of silica gold (SiO2:Au) core/shell nanoparticles (NPs) deposited using the layer-by-layer (LbL) method, was employed for the development of a bio-sensor. The SiO2:Au NPs were electrostatically assembled onto the LPG with the aid of a poly(hydrochloridemonium) (PAH) polycation layer. The LPG sensor operates at the phase matching turning point to provide the highest sensitivity. The SiO2:Au NPs were modified with biotin, which was used as a ligand for streptavidin (SV) detection. The sensing mechanism is based on the measurement of the refractive index change induced by the binding of the SV to the biotin. The lowest detected concentration of SV was 19 nM using an LPG modified with a 3 layer (PAH/SiO2:Au) thin film.

P32/Paper 9157-290

Optical fiber refractometers based on localized surface plasmon resonance (LSPR) and lossy mode resonance (LMR) Pedro J. Rivero, Miguel Hernaez, Javier Goicoechea, Ignacio R. Matias, Francisco J. Arregui, Univ. Pública de Navarra (Spain)

An optical fiber device showing simultaneously two optical phenomena, localized surface plasmon resonance (LSPR) and lossy mode resonance (LMR), is presented here for the first time. It consists of a fragment of stripped optical fiber coated with a polymeric film that includes gold nanoparticles. The absorption peaks related to both phenomena were captured during the deposition of the coating, showing a different evolution. In addition, the behavior of both phenomena to variations of the surrounding medium refractive index (SMRI) was monitored, studying the different responses of LSPR and LMR.

P33/Paper 9157-298

A high sensitivity refractometer based on a tapered SCSMF structure and its application to biosensing Qiang Wu, Youqiao Ma, Yuliya Semenova, Dublin Institute of Technology (Ireland); Jinhui Yuan, Beijing Univ. of Posts and Telecommunications (China); Lin Bo, Pengfei Wang, Dublin Institute of Technology (Ireland); Xinzhu Sang, Mianzhen Teng, Chongxiu Yu, Beijing Univ. of Posts and Telecommunications (China); Christy C. O'Mahony, Dublin City Univ. (Ireland); Gerald Farrell, Dublin Institute of Technology (Ireland)

A high sensitivity refractive index (RI) sensor based on a tapered small core singlemode fibre (SCSMF) structure is proposed and developed. By tapering the SCSMF section, this sensor has very high sensitivity around the RI of water. Experimentally we have demonstrated a sensitivity of 1988.5 nm/RIU (RI unit) in the RI range from 1.3325 to 1.3407 by tapering a SCSMF section from a diameter of 125 µm to a diameter of 16 µm. The feasibility of using this type of sensor for biosensing application has also been verified by experiments. This was undertaken using a suitable Fibrinogen antigen surface functionalisation, which successfully showed that the sensor can in principle detect differences in the concentration of a Fibrinogen antibody.

P34/Paper 9157-301

Measuring water activity of aviation fuel using a polymer optical fiber Bragg grating

Wei Zhang, David J. Webb, Aston Univ. (United Kingdom); Mark Carpenter, Colleen Williams, Defence Academy of the United Kingdom (United Kingdom)

Poly(methyl methacrylate) (PMMA) based polymer optical fiber Bragg gratings have been used for measuring water activity of aviation fuel. Jet A-1 samples with water content ranging from 100% ERH (wet fuel) to 10 ppm (dried fuel), have been conditioned and calibrated for measurement. The PMMA based optical fiber grating exhibits consistent response and a good sensitivity of 59±3pm/ppm (water content in mass). This water activity measurement allows PMMA based optical fiber gratings to detect very tinyounts of water in fuels that have a low water saturation point, potentially giving early warning of unsafe operation of a fuel system.

P35/Paper 9157-305

Design and synthesis of a fluorescent molecular imprinted polymer for use in an optical fibre-based cocaine sensor Stephen P. Wren, City Univ. London (United Kingdom); Sergey A. Piletsky, Kal Karim, Univ. of Leicester (United Kingdom); Paul Gascoine, Smiths Detection (United Kingdom); Richard Lacey, Ctr. for Applied Science and Technology (United Kingdom); Tong Sun, Kenneth T. V. Grattan, City Univ. London (United Kingdom)

Previously, we have developed chemical sensors using fibre optic-based techniques for the detection of Cocaine, utilising molecularly imprinted polymers (MIPs) containing fluorescein moieties as the signalling groups. Here, we report the computational design of a fluorophore which was incorporated into a MIP for the generation of a novel sensor that offers improved sensitivity for Cocaine with a detection range of 1-100microM. High selectivity for Cocaine over a suite of known Cocaine interferants (25 microM) was also demonstrated by measuring changes in the intensity of fluorescence signals received from the sensor. P36/Paper 9157-315

Interferometric microstructured polymer optical fiber ultrasound sensor for optoacoustic endoscopic imaging in biomedical applications Daniel C. Gallego, Univ. Carlos III de Madrid (Spain); David Sáez-Rodríguez, David Webb, Aston Univ. (United Kingdom); Ole Bang, DTU Fotonik (Denmark); Horacio Lamela, Univ. Carlos III de Madrid (Spain)

We report a characterization of the acoustic sensitivity of microstructured polymer optical fiber interferometric sensors at ultrasonic frequencies from 100kHz to 10MHz. The use of wide-band ultrasonic fiber optic sensors in biomedical ultrasonic and optoacoustic applications is an open alternative to conventional piezoelectric transducers. These kind of sensors, made of biocompatible polymers, are good candidates for the sensing element in an optoacoustic endoscope because of its high sensitivity, its shape and its non-brittle and non-electric nature. The acoustic sensitivity of the intrinsic fiber optic interferometric sensors depends strongly of the material which is composed of. In this work we compare experimentally the intrinsic ultrasonic sensitivities of a PMMA mPOF with other three optical fibers: a single-mode silica optical fiber, a single-mode polymer optical fiber and a multimode graded-index perfluorinated polymer optical fiber.

P37/Paper 9157-344

Analysis of organic solvents and liquid mixtures using a fiber-tip evaporation sensor Eyal Preter, Bar-Ilan Univ. (Israel); Denis Donlagic, Univ. of Maribor (Slovenia); Vlada Artel, Bar-Ilan Univ. (Israel); Rachel A. Katims, Binghamton Univ. (United States); Chaim N. Sukenik, Avinoam Zadok, Bar-Ilan Univ. (Israel)

The instantaneous size and rate of evaporation of pendant liquid droplets placed on the cleaved facet of a standard fiber are reconstructed based on reflected optical power. Using the evaporation dynamics, the relative contents of ethanol in ethanol-water binary mixtures are assessed with 1% precision and different blends of methanol in gasoline are properly recognized. The latter application, in particular, is significant for the use of alternative fuels in the automotive sector. Also, ten organic solvents are identified based on their evaporation from a fiber facet coated with a hydrophobic, self-assembled monolayer. P38/Paper 9157-385

In-situ detection of DNA hybridization with a microfiber Bragg grating biosensor Dandan Sun, Guo Tuan, Xiaodong Xie, Yang Ran, Yunyun Huang, Bai-ou Guan, Jinan Univ. (China)

Microfiber Bragg gratings (mFBGs) can be used as cost-effective and relatively simple-to-implement biosensors for monitoring DNA interactions in situ. The sensors are functionalized by a monolayer of poly-L-lysine (PLL) with the specific molecular recognition probe DNA sequences to bind with high specificity to a given target. By recording the wavelength seperation between the two resonant peaks of a single mFBG, the mFBG biosensor is capable of detecting the presence of specific target DNA in situ.

P39/Paper 9157-414

Experimental investigation of Long period grating working in transition mode Luis B. Melo, Geoff Burton, Stephen Warwick, Peter Wild, Univ. of Victoria (Canada)

An experimental investigation of the transition modes of long period gratings (LPG) is reported. Coating LPGs with a material of high refractive index causes a reorganization of the cladding modes, leading to a substantial increase in sensitivity to changes in the surrounding refractive index (SRI). The thickness of polystyrene coatings on optical fibers, applied by dip-coating, was measured by scanning electron microscopy. The maximum sensitivity and corresponding SRI of each coating thickness was then determined by analyzing the attenuation bands in the transmission spectrum

P40/Paper 9157-424

Ultrasensitive refractive index sensor based on elliptic microfibers fabricated by CO2 laser Lipeng Sun, Jie Li, Long Jin, Bai-Ou Guan, Jinan Univ. (China)

A highly-birefringent elliptic microfiber is fabricated by use of the CO2-laser machining and fusion tapering methods. The fiber ellipse can be well controlled with modification of the CO2 laser output power. Both positive and negative sensitivities are observed for the structure to be used in the refractive index sensing application, in contrast to the previously-reported microfiber devices. Moreover, the maximum obtained sensitivity is as high as 195348nm/RIU (refractive index unit) around refractive index of 1.35887, which is one order of magnitude higher than other microfiber counterparts. The temperature-cross sensitivity of 0.007nm/℃ is quite low. P41/Paper 9157-464

Selective Sensing of Alcohols in Water Influenced by Zeolite Coatings on Optical Fiber Marziyeh Nazari, Victoria Univ. (Australia), CSIRO Materials Science and Engineering (Australia); Matthew R. Hill, CSIRO (Australia); Mikel Duke, Fotios Sidiroglou, Stephen F. Collins, Victoria Univ. (Australia)

The application of a MFI type zeolite coating on the end of an optical fiber is presented. Zeolite coatings were directly grown on the freshly cleaved endface of optical fibers. It was found that the produced integrated zeolite-fiber sensors exhibit specific chemical sensitivity towards certain chemicals. The molecular adsorption induced change of zeolite refractive index was studied to understand the sensing mechanisms of the developed sensor system. This work can lead to a new class of portable zeolite thin film enabled miniaturized fiber optic sensors. P42/Paper 9157-513

Fiber enhanced Raman spectroscopy Torsten Frosch, Di Yan, Stefan Hanf, Juergen Popp, Institut für Photonische Technologien e.V. (Germany)

Fiber enhanced Raman sensing is presented for versatile and extremely sensitive analysis of pharmaceutical drugs and biogenic gases. Elaborated micro-structured optical fibers guide the light with very low losses within their hollow core and provide at the same time a miniaturized sample container for the analytes. Thus, fiber enhanced Raman spectroscopy (FERS) allows for chemically selective detection of minimal sampleounts with high sensitivity. Two examples are presented in this contribution: (i) the detection of picomolar concentrations of pharmaceutical drugs; and (ii) the analysis of biogenic gases within a complex mixture of gases with analytical sensitivities in the ppm range. P43/Paper 9157-517

Spectral-domain OCT imaging using a spectrally flexible wavelength-swept fiber laser based on dispersion tuning Yuya Takubo, Shinji Yamashita, The Univ. of Tokyo (Japan)

The broadband source with the arbitrary spectrum based on dispersion tuning technique was demonstrated. While a dispersion-tuned wavelength-swept laser is capable of fast and widely wavelength sweep, it can also be used as a broadband spectrally-flexible source by controlling the sweep waveform. It is the first demonstration of spectrally-tunable source to the best of our knowledge. We used the dispersion-tuned laser as a broadband source for SD-OCT system by synchronizing sweep rate of a laser and exposure time of a CCD camera in SD-OCT system. We successfully obtained the images of an adhesive tape and a human finger. P44/Paper 9157-518

UV resonance Raman sensing of pharmaceutical drugs in hollow Fibers Di Yan, Juergen Popp, Torsten Frosch, Institut für Photonische Technologien e.V. (Germany)

We report about the experimental combination of UV resonance Raman sensing (UV-RRS) and fiber enhanced Raman sensing (FERS) on pharmaceuticals. The results show that the chemical sensitivity is highly improved and at the same time the sample volume is reduced compared to conventional measurements. A hundreds-fold improvement of the limit of detection (LOD) has been achieved with the combination of resonance Raman enhancement and fiber enhancement. The enhanced Raman signal has a reliable linear relationship with the concentration of the analyte, and therefore shows great potential for quantitative analysis of pharmaceuticals. P45/Paper 9157-522

Fiber-optical particle sizing by photon density wave spectroscopy Lena Bressel, Marvin Münzberg, Roland Hass, Oliver Reich, Univ. Potsdam (Germany)

Photon Density Wave (PDW) spectroscopy is introduced as a fiber-optical technique for the in-line and dilution-free determination of the droplet or particle size in highly turbid emulsions and suspensions, respectively. Here, focus is laid on the monitoring of the Phase Inversion Temperature (PIT) emulsification process. The different stages like the inversion from an oil-in-water to a water-in-oil macroemulsion and finally to an oil-in-water nanoemulsion are observed and the droplet size is determined with high temporal resolution. This process shows the capability of PDW spectroscopy to determine particle or droplet sizes over a wide range from the nanometer to micrometer scale. P46/Paper 9157-559

Bacteriophage adhesin-coated long-period gratings for bacterial lipopolysaccharide recognition

Marcin Koba, Univ. du Québec en Outaouais (Canada); Mateusz Śmietana, Warsaw Univ. of Technology (Poland); Ewa Brzozowska, Institute of Immunology and Experimental Therapy (Poland); Predrag Mikulic, Wojtek J. Bock, Univ. du Québec en Outaouais (Canada)

In this work we report an application of the optical fiber long-period gratings (LPGs) working near the dispersion turning point of higher order cladding modes for bacterial lipopolysaccharide (LPS) recognition. We show that when the LPG is functionalized with the bacteriophage adhesin, it is capable of very specific LPS detection. Thus, we compare label-free binding effect for specific to the adhesin LPS-positive and non-specific LPS-negative. The resonance wavelength shift induced by the LPS-positive reaches 2.9 nm, while for LPS-negative the shift is negligible. The LPG-based sensing structure allows for monitoring of the binding phenomenon in real time and with good accuracy. P47/Paper 9157-565

Highly sensitive evanescent-wave water salinity sensor realized with rectangular optical microfiber Sagnac interferometer Chuang Wu, Lipeng Sun, Jie Li, Bai-Ou Guan, Jinan Univ. (China)

We demonstrated a highly sensitive evanescent-wave-based water salinity sensor using a rectangular optical microfiber Sagnac interferometer. The microfiber has a rectangular cross-section with widths of 4.0 μm by 2.5 μm and total length of 36 mm. For water salinity from 0‰ to 40‰, a high sensitivity of 1.95 nm/(1‰) was achieved at the wavelength of 1550 nm, indicating a detection limit of 0.01‰. The proposed sensor has advantages of high sensitivity, compact size, ease for fabrication, and potentially low-cost. It is very useful for undersea applications and manufacture process controlling where monitoring small change in water salinity is required. P48/Paper 9157-586

SPR sensors in POF: a new experimental configuration for extended refractive index range and better SNR Nunzio Cennamo, Seconda Univ degli Studi di Napoli (Italy); Luis Coelho, INESC Porto (Portugal); Ariel Guerreiro, Univ. do Porto (Portugal), INESC Porto (Portugal); Pedro A. S. Jorge, INESC Porto (Portugal); Luigi Zeni, Seconda Univ degli Studi di Napoli (Italy)

In this work we present a new low cost SPR (Surface Plasmon Resonance) sensor configuration based on efficient higher-order mode filtering in plastic multimode fibers, using a tapered POF (Plastic Optical Fiber) after the sensor system, without decreasing the sensitivity of the sensor. In particular, we present the experimental results obtained with this new configuration. The experimental results have shown as the tapered POF after the sensor system influences the performances in terms of refractive index range and Signal-to-Noise Ratio (SNR).

P49/Paper 9157-607

Optical fiber refractometer based on silicon nitride nano-overlay deposited with PECVD method Bartosz Michalak, Mateusz J. Smietana, Warsaw Univ. of Technology (Poland); Marcin Koba, Warsaw Univ. of Technology (Poland), National Institute of Telecommunications (Poland)

This work presents an application of polymer-clad silica (PCS) multimode optical fiber coated with high refractive index (nD>2.4) silicon nitride (SiNx) nano-overlay for refractive index (RI) sensing. The nano-overlay was deposited on 2.5 mm-long section of the fiber’s core using radio-frequency plasma-enhanced chemical vapor deposition (RF PECVD) method. We show that spectral response of the sensor to external RI strongly depends on the overlay deposition time. For just 6 min-long process the sensitivity calculated as a shift of the resonance observed in the transmission spectrum at about λ=600 nm with RI reaches 690 nm/RIU. The experimental results have been compared to numerical simulations.

P50/Paper 9157-611

Nitrogen dioxide detector based on femtosecond TFBG coated with LuPc2 in P(S-bMMA) polymer matrix Antonio Bueno, Univ. de Mons (Belgium); Driss Lahem, MateriaNova (Belgium); Marc Debliquy, Christophe Caucheteur, Patrice Mégret, Univ. de Mons (Belgium)

In this work, we present the results of the tests for NO2 detection using tilted fiber Bragg gratings (TFBGs) inscribed with a pulsed femtosecond laser and coated with the polymer P(S-b-MMA) and the NO2 sensitive molecule LuPc2. Two coating methods were carried out: using a porous and a non-porous polymer matrix. The results show that a previous treatment to create pores in the polymer matrix achieves a faster response but also a lower sensitivity compared to the non-porous matrix.

P51/Paper 9157-640

Highly sensitive and selective optical fiber fluorescence sensor for lead ion detection in water using corrugated long period fiber grating Yasser Chiniforooshan, Jianjun Ma, Wojtek J. Bock, Univ. du Québec en Outaouais (Canada); Wenhui Hao, Wayne Z. Y. Wang, Carleton Univ. (Canada)

Optical fiber fluorescence sensors are widely used for chemical sensing. Intrinsic fluorescence sensors such as evanescent-wave sensors can be used for surface sensing while extrinsic sensors are used for bulk sensing. In intrinsic/ extrinsic fluorescence sensors, typically the side-wall/end-face of a single/multi-mode fiber is used. In this paper we introduce a novel intrinsic optical fiber fluorescence sensor which uses the side-wall of a large-core multi-mode fiber to collect the fluorescence from the bulk of samples. The method is to use a corrugated long period fiber grating, fabricated by a CO2 laser, to couple radiating modes to the core modes. Using the side-wall of a fiber helps to fabricate a multi-target or a distributed sensor. We also report the sensing of lead ions with concentration as low as few ppb in water using a novel fluorescence turn-on polymer as a chemical probe.

P52/Paper 9157-646

Intradiscal pressure variation under spontaneous ventilation Paulo Roriz, INESC Porto (Portugal); J. Ferreira, Univ. do Porto (Portugal); J. C. Potes, M. T. Oliveira, Univ. of Évora (Portugal); José Luís C. Santos, Jose Simões, Orlando Frazão, INESC Porto (Portugal)

The pressure measured in the intervertebral discs is a response to the loads acting on the spine. External loads, such as the reaction forces resulting from locomotion, manual handling and collisions are probably the most relevant in studying spine trauma. However, the physiological functions such as breathing and hearth rate also participate in subtle variations of intradiscal pressure that can be observed only in vivo at resting. Present work is an effort to measure the effect of breathing on intradiscal pressure of an anesthetized sheep.

P53/Paper 9157-651

Analysis of phase interrogation of SPR fiber optic sensors with characteristics tailored by the application of different metal-dielectric overlays Hamed Moayyed, Ivo T. Leite, INESC TEC (Portugal); Luis Coelho, José Luís Campos Oliveira Santos, Ariel Guerreiro, INESC TEC (Portugal), Univ. do Porto (Portugal); Diana Viegas, INESC TEC (Portugal), Cabelte, S.A. (Portugal)

Optical fiber sensors based on the phenomenon of plasmonic resonance can be interrogated applying different methods, the most common one being the spectral approach where the measurand information is derived from the reading of the wavelength resonance dip. In principle, a far better performance can be achieved considering the reading of the phase of the light at a specific wavelength located within the spectral plasmonic resonance. This approach is investigated in this work for fiber optic SPR sensors with overlays which are combinations of metallic and dielectric thin films, permitting not only to tune the wavelength of the SPR resonance but also the sensitivity associated with the phase interrogation of the sensors. P54/Paper 9157-653

Stack of PECVD silicon nitride nano-films on optical fiber end-face for refractive index sensing Mateusz J. Smietana, Marcin Koba, Radoslaw Rozycki-Bakon, Warsaw Univ. of Technology (Poland)

This paper presents a stack of silicon nitride (SiNx) nano-films deposited with radio-frequency plasma-enhanced chemical deposition (RF PECVD) method on single-mode fiber end-face for refractive index (RI) sensing. The stack consist of high (n~2.4) and low (n~1.9) refractive index (at λ=1550 nm) SiNx nano-films arranged alternately. As a result of the experiment where 5 nano-layers were deposited, we received down to -30 dB-deep resonance in reflection spectrum at about λ=1550 nm. In the proposed sensing scheme both reflected power and wavelength of the resonance can be used for external RI measurements.

P55/Paper 9157-656

Reflection-type long period grating biosensor for the detection of drug resistant bacteria: The Opto-bacteria Project Marco Consales, Giuseppe Quero, Univ. degli Studi del Sannio (Italy); Simona Zuppolini, Lucia Sansone, Anna Borriello, CNR, Institute of Molecular and Cell Biology (Italy); Michele Giordano, Optosmart S.r.l. (Italy); Alberto Venturelli, Tydock Pharma S.r.l (Italy); Andrea Cusano, Univ. degli Studi del Sannio (Italy)

We report on the development of a multilayer coated reflection-type long period fiber grating (LPG) biosensor, useful for the detection of antibiotic resistance bacteria. A standard LPG is first transformed in a more practical probe working in reflection mode, then it is coated by a primary layer of aPS and a secondary layer of PMMA in order to increase its surrounding refractive index sensitivity and at the same time provide the necessary conditions for a correct bio-functionalization. Standard linkage chemistry has been applied to anchor the bioreceptors on the probe surface. We show some preliminary results demonstrating the capability of our LPG biosensor to successfully monitor all the biological steps of the biomolecular experiments, including β-lactamase binding detection tests. P56/Paper 9157-662

OCT assessment of aortic wall degradation for surgical guidance Eusebio Real, University of Cantabria (Spain); José Fernando Val-Bernal, Alejandro Pontón, Marta Calvo Díez, Marta Mayorga, José Manuel Revuelta, Marqués de Valdecilla Univ. Hospital (Spain), University of Cantabria (Spain); José Miguel López-Higuera, Olga María Conde, University of Cantabria (Spain)

The degradation of the wall in large cardiovascular vessels, such as the aorta artery, induces weakness in the vessel that can lead to the formation of aneurysms and the rupture of the vessel. Characterization of the wall integrity is assessed by OCT for future intraoperative assistance in aneurysm graft surgery interventions. Optical Coherence Tomography (OCT) provides cross sectional

images of the wall of the aortic media layer. Wall degradations appear as spatial anomalies in the reflectivity profile through the wall thickness. Wall degradation assessment is proposed by automatic identification and dimensioning of these anomalies within the homogeneous surrounding tissue. P57/Paper 9157-669

Optical fibre cantilever sensor for biological application Jun Li, Yaxian Zhou, Gareth Patterson, Will Shu, Robert R. J. Maier, Ruther Fowler, Duncan P. Hand, William N. Macpherson, Heriot-Watt Univ. (United Kingdom)

Micro-cantilever sensors have shown great promise in a wide range of application are as including chemical and biological sensing. However, many of these devices are based upon a sensor ‘chip’ that requires careful alignment between the cantilever and the read-out system, which can be challenging. Furthermore, optical interrogation typically involves a bulky free-space system. Optical fibre addressed cantilevers have been reported previously in the literature and in this paper we propose techniques to design and fabricate polymer micro-cantilevers for attachment onto the end of standard single mode fibres using laser machining. Low-cost optical sources and a fibre coupled spectrometer are employed to monitor the cantilever deflection and therefore observe biological binding between a species of interest and an activated cantilever. Proof-of-concept experiments show that the sensor is capable of detecting pathogen concentration with down to a level of 10E5 cfu /ml.

P58/Paper 9157-507

The magnitude of a Human bite measured exactly at the molar Intercuspidation using FBG Maura S. Milczewski, Hypolito J. Kalinowski, Ilda Abe, Univ. Tecnológica Federal do Paraná (Brazil)

The aim of the study is to develop a new punctual method to determine the human bite force, between uppers and lowers first molars, at the moment of occlusion in maximum intercuspation. Fibre optic Bragg gratings are encapsulated in an acetate splint made by casting of a volunteer lower dentition. Splint sensor was positioned into the mouth to be pressured with minimal occlusal interference. The transversal pressure on the FBG was acquired at the moment of before occlusion (free), occlusion and biting. The measured forces were 12N during occlusion and 28N bite force, between right uppers and lowers first molars.

P59/Paper 9157-36 Brillouin distributed sensor over a 200km fiber-loop using a dual-pump configuration and colour coding Sébastien Le Floch, F. Sauser, M. Llera, Haute Ecole Arc Ingénierie Siège (Switzerland); E. Rochat, Omnisens SA (Switzerland)

In this paper, we propose a new Brillouin Optical Time Domain Analysis (BOTDA) set-up that combines simultaneous Brillouin gain/loss measurements with colour coding. This technique gives the advantage that the pump power can greatly be increased, compared to other coding schemes, thus increasing the sensing range. A measurement over a 200 km fiber-loop is performed, with a 3 meter spatial resolution and an accuracy of 3 MHz at the end of the sensing fiber. To the best of our knowledge, this is the best result obtained with a Brillouin sensor without Ramanplification.

P60/Paper 9157-42

Cyclic pulse coding for hybrid fast BOTDA/Raman sensor Yonas Muanenda, Mohammad Taki, Iacopo Toccafondo, Alessandro Signorini, Tiziano Nannipieri, Claudio Oton, Fabrizio Di Pasquale, Scuola Superiore Sant'Anna (Italy)

We propose and experimentally demonstrate a fully hybrid distributed sensing scheme that uses a single narrow-band laser to perform fast measurement of the BFS using BOTDA and simultaneous temperature measurement based on spontaneous Raman scattering over 10 km of single mode fiber. The use of cyclic pulse coding effectively reduces the pump peak power levels required for accurate Raman-based distributed temperature measurement, enhancing at the same time the speed of the BFS measurement in the BOTDA technique.

P61/Paper 9157-52

A fast, high-spatial-resolution Raman distributed temperature sensor A. H. Hartog, Y. Chen, R. J. Marsh, I. M. Hilton, M. R. Hadley, Patrick A. Ross, Schlumberger Fiber-Optic Technology Ctr. (United Kingdom)

Conventional high-spatial-resolution Raman distributed temperature sensing (DTS) systems are based on photon-counting techniques, which result in slow measurements over short sensing fibers. We describe an alternative approach that uses a high-power, short-pulse-width laser and provides fast measurements over fibers longer than 1 km. We demonstrate measurements with 1-s update times over fiber lengths greater than 1 km with better than 0.4-m spatial resolution. We introduce a figure of merit for DTS and we show a substantial improvement (x 100) over earlier results.

P62/Paper 9157-53

Distributed vibration sensing on optical fibre: field testing in borehole seismic applications

A. H. Hartog, Schlumberger Fiber-Optic Technology Ctr. (United Kingdom); B. Frignet, Services Techniques Schlumberger (France); Duncan Mackie, Schlumberger Evaluation and Production Services (United Kingdom); O. I. Kotov, Leonid B. Liokumovich, St. Petersburg State Polytechnical Univ. (Russian Federation)

We describe the measurement of seismic waves in a borehole using distributed vibration sensing conveyed on wireline cable. The optical measurement is compared directly with the results of a multi-level borehole seismic survey with conventional electrical accelerometers. P63/Paper 9157-99

A novel intrusion signal processing method for phase-sensitive optical time-domain reflectometry (θ-OTDR) Huijuan Wu, Xiaoyu Li, Zhengpu Peng, Yunjiang Rao, Univ. of Electronic Science and Technology of China (China)

Phase-sensitive Optical-Time-Domain Reflectometry (Φ-OTDR) is a useful distributed fiber-optic sensing technology to detect and locate multiple dynamic disturbances, offering a cost-effective and sensitive solution for intrusion monitoring of long perimeters. The Φ-OTDR is affected by laser frequency drift, air movement, transient acoustic interference and environmental noises. resulting in high Nuisance Alarm Rates (NARs). In this paper, we proposed a novel intrusion signal processing method based on the singular spectrum analysis of the longitudinal time sequence of the Φ-OTDR. The experimental results shows that true intrusions can be correctly distinguished from varying background noises and sound or air movement interferences. The probability for correct detection can be improved up to ~94% and false alarm rate can be controlled as low as ~6%. P64/Paper 9157-103

154.4km BOTDA based on hybrid distributed Ramanplifications Yunjiang Rao, Xin-Hong Jia, Zi-Nan Wang, Wei-Li Zhang, Cheng-Xu Yuan, Jin Li, Xiao-Dong Yan, Han Wu, Ye Yu Zhu, Fei Peng, Univ. of Electronic Science and Technology of China (China)

Ultra-long-distance distributed fiber-optic sensing based on Brillouin optical time-domain analysis (BOTDA) is achieved by using a proposed configuration of hybrid distributed Ramanplification (H-DRA), that is realized by incorporating random fiber laser (RFL) based 2nd-order pump and low-noise laser-diode (LD) based 1st-order pump. A repeater-less sensing distance of up to 154.4km with 5m spatial resolution and ~±1.4℃ temperature uncertainty is successfully demonstrated, which is the longest repeater-less BOTDA reported to date. P65/Paper 9157-122

Evaluating distributed fibre optic sensors integrated into thermoplastic composites for structural health monitoring Constanze Schilder, Marcus Schukar, Milan Steffen, Katerina Krebber, Bundesanstalt für Materialforschung und -prüfung (Germany)

Strain sensors used for structural health monitoring (SHM) must provide reliable measurement data during their entire service lifetime. To achieve this for fibre optic sensors integrated into composites, the integration of the sensor has to be adapted according to the process conditions. This paper describes the fabrication of thermoplastic composite samples with integrated distributed fibre optic sensors (DFOS) based on copper-nickel and polyimide coated silica optical fibres. The performance of these DFOS as SHM sensors is evaluated in terms of reliability by measurements derived from comparative measurements with resistance strain gauges and from fatigue tests with 10 million load cycles. P66/Paper 9157-152

Motion compensation in distributed fiber optic sensing via optical frequency domain reflectometry Joseph J. Bos, Nur Aida Abdul Rahim, Luna Innovations Inc. (United States)

We demonstrate a novel algorithm for removing adverse effects of motion in distributed sensing measurements via Optical Frequency Domain Reflectometry (OFDR), using Rayleigh backscatter from low-bend loss fiber as the transducer. Vibrationplitudes and frequencies of 2.5 Gs and up to 50 Hz, respectively, were corrected for in real-time while measuring up to 10,000 microstrain. Results show 99.3% recovery of motion-affected strain data while maintaining 0.3% accuracy and 5 mm spatial resolution. Measurement acquisition rates were 23.8 Hz and 100 Hz. These results demonstrate that OFDR may be used in dynamic environments to provide accurate and high-resolution, distributed strain measurements.

P67/Paper 9157-177

Modelling the depletion length induced by modulation instability in distributed optical fibre sensors Mehdi Alem, Marcelo A. Soto, Luc Thévenaz, Ecole Polytechnique Fédérale de Lausanne (Switzerland)

An analytical model for the depletion length of modulation instability in single-mode optical fibres is proposed. The model gives the possibility to determine the maximum sensing distance that distributed optical fibre sensors can reach before being limited by the pump depletion induced by modulation instability. The important role of the noise level in the evolution of both modulation instability and the respective power depletion is clarified. The model gives a closed-form expression helpful for a predictive design and is validated comparing the analytical results obtained by the model with measurements in a 25 km long Brillouin fibre sensor.

P68/Paper 9157-188

Enhanced response in Brillouin distributed optical fibre sensors by simultaneous time and frequency pump multiplexing Marcelo A. Soto, Ecole Polytechnique Fédérale de Lausanne (Switzerland); Amelia L. Ricchiuti, Univ. Politècnica de València (Spain); Liang Zhang, Ecole Polytechnique Fédérale de Lausanne (Switzerland); David Barrera, Salvador Sales, Univ. Politècnica de València (Spain); Luc Thévenaz, Ecole Polytechnique Fédérale de Lausanne (Switzerland)

A technique to enhance the response of Brillouin distributed sensors is proposed and experimentally validated. The method consists in creating a multi-frequency pump pulse interacting with a multi-frequency continuous-wave probe. The power of each pulse at a distinct frequency is lower than the threshold for nonlinear effects, while the sensor response remains given by the total power of all pulses. Distinct frequency pulses are delayed to avoid temporal overlapping and cross-interaction; this requires to smartly reconstruct the traces before photo-detection. The method is validated in a 50 km-long sensor using 3 frequencies, demonstrating a signal-to-noise ratio enhancement of 4.8 dB. P69/Paper 9157-215

Phasorial DPP-BOTDA sensor tolerant to non-local effects Javier Urricelqui, Jon Mariñelarena, Mikel Sagues, Alayn Loayssa, Univ. Pública de Navarra (Spain)

We introduce a modification of the differential pulse-width pair technique in a BOTDA sensor based on a phase modulated probe wave and RF demodulation. This provides a differential Brillouin phasorial signal with high spatial and spectral resolution in both components (magnitude and phase-shift). Moreover, the use of a phase modulated probe wave provides RF phase-shift measurements tolerant to the emergence of non-local effects. The combination of both techniques can lead to the development of long-range BOTDA sensors. Proof-of-concept experiments demonstrate RF phase-shift measurements with 1m spatial resolution over 50km and an uncertainty of 1.3ºC at the worst contrast position. P70/Paper 9157-216

First observation of Brillouin scattering in tapered plastic optical fiber Neisei Hayashi, Hideyuki Fukuda, Yosuke Mizuno, Kentaro Nakamura, Tokyo Institute of Technology (Japan)

We report on the first observation of the Brillouin gain spectrum in a perfluorinated graded-index polymer optical fiber (POF) tapered by a heat-and-pull technique. The Stokes power was slightly enhanced by tapering probably on account of higher optical power density in the core. In addition, the Brillouin frequency shift was decreased by ~40 MHz, which was experimentally verified to be partially caused by high heating temperature applied to the POF during the taper fabrication process. We anticipate that our findings will provide a basic principle of temperature sensing with “memory” function. P71/Paper 9157-224

Distributed optical fiber sensors for integrated monitoring of railway infrastructures Aldo Minardo, Agnese Coscetta, Seconda Univ degli Studi di Napoli (Italy); Giuseppe Porcaro, Tecnomatica SaS (Italy); Daniele Giannetta, Ferrovie del Gargano, Direzione di Esercizio (Italy); Romeo Bernini, CNR-IREA (Italy); Luigi Zeni, Seconda Univ degli Studi di Napoli (Italy)

We propose the application of a distributed optical fiber sensor based on stimulated Brillouin scattering, as an integrated system for safety monitoring of railway infrastructures. The strain distribution was measured dynamically along a 60 meters length of rail track, as well as along a 3-m stone arch bridge. The results indicate that distributed sensing technology is able to provide useful information in railway traffic and safety monitoring. P72/Paper 9157-244

High-performance in-line Brillouin optical correlation domain analysis Ji Ho Jeong, Korea Institute of Science and Technology (Korea, Republic of), Korea Institute of Science and Technology (Korea, Republic of); Kwang Yong Song, Chung-Ang Univ. (Korea, Republic of); Sang Bae Lee, Kwanil Lee, Korea Institute of Science and Technology (Korea, Republic of)

A high-performance single-ended correlation-domain Brillouin sensor is demonstrated. Large DC noise induced by direct reflection of Brillouin pump was successfully removed by the phase modulation-based differential measurement as well as additional 4-fold enhancement in the spatial resolution. By applying an intentional loss to the end of a sensing fiber one of two correlation peaks within the fiber is suppressed, leading to double enlargement of the measurement range compared to former in-line reflector based systems. In the experimental confirmation a distributed strain measurement with a range of 100 m and a spatial resolution of 5 cm is presented. P73/Paper 9157-248

Multi-wavelength erbium fiber ring laser with optical feedback for temperature measurements Silvia Diaz, Daniel Leandro, Manuel Lopez-Amo, Univ. Pública de Navarra (Spain)

In this work, a new configuration of a multi-wavelength erbium fiber ring laser is proposed and demonstrated experimentally by introducing a feedback fiber loop in a fiber ring cavity. Four-wavelength laser emission lines were obtained simultaneously in single-longitudinal mode operation showing a power instability lower than 0.56 dB, and an optical signal-to-noise ratio higher than 50 dB for all the emitted wavelengths. The sensing capability of the FBGs gives this source the possibility to be also used as sensor-network multiplexing scheme. The system offers a better stability and higher optical signal to noise ratios than similar configurations.

P74/Paper 9157-257

124km phase-sensitive OTDR with Brillouinplification Jin Li, Zinan Wang, Li Zhang, Fei Peng, Shunkun Xiao, Huijuan Wu, Yunjiang Rao, Univ. of Electronic Science and Technology of China (China)

A long-range (124km) fully distributed fiber-optic vibration sensing system is demonstrated, based on phase-sensitive optical time-domain reflectometry (Φ-OTDR) with counter-pumping distributed fiber Brillouinplification (FBA). FBA significantly enhances the probe pulse signal at the second half of the sensing fiber with less than 10dBm pump power, and itsplification efficiency is demonstrated to be much higher than 26.9dBm counter-pumping Ramanplification. As a result, demodulated intrusion signals along the whole sensing range can keep high signal to noise ratio. The FBA scheme demonstrated in this work can also be incorporated in many other distributed fiber-optic sensing systems for extension of sensing distance. P75/Paper 9157-261

Interrogation system for fiber loop mirror sensors using OTDR Maria Thereza M. Rocco Giraldi, Military Institute of Engineering (Brazil), INESC Porto (Portugal); Cindy S. Fernandes, Univ. Federal do Pará (Brazil), INESC Porto (Portugal); Marta S. Ferreira, INESC Porto (Portugal), Univ. do Porto (Portugal); João C. W. Costa, Univ. Federal do Pará (Brazil); José Luís C. Santos, Orlando Frazão, INESC Porto (Portugal), Univ. do Porto (Portugal) .

In this paper it is proposed an interrogation system based on OTDR for fiber loop mirror intensity sensors. The system has been characterized in order to obtain its maximum dynamic range. The technique demonstrated good linearity with a – 13.3 dB/mm slope. A 0.027 mm resolution was achieved. The proposed interrogation system permits multiplexing of around 10 sensors and showed to be an alternative technique for multiplexing and remote sensing. P76/Paper 9157-284

Real distributed vibration sensing with high frequency response based on pulse pair Qian He, Tao Zhu, Xianghui Xiao, Dongmei Diao, Wei Huang, Chongqing Univ. (China); Xiaoyi Bao, Univ. of Ottawa (Canada)

In conventional phase-sensitive optical time domain reflectometry (φ-OTDR), the length of sensing fiber mainly determines the repetition rate of probe light pulses, which limits the extent of detectable frequency range. Moreover, averaging method, which is adopted to enhance the location signal-to-noise-ratio (SNR), further decreases the maximum detectable frequency. This paper demonstrates a distributed vibration sensor with satisfied location SNR and extended frequency response range by using a probe pulse pair with a frequency difference. Experimental results show that this method is able to break the trade-off between the given sensing fiber length and the traditional maximum detectable frequency response of φ-OTDR system. P77/Paper 9157-285

High sensitive micro-displacement intensity fiber sensor by using a multiwavelength erbium doped fiber ring laser based on optical add-drop multiplexers Rosa Ana Perez-Herrera, Daniel Leandro, Manuel Lopez-Amo, Univ. Pública de Navarra (Spain)

In this work, a wavelength division multiplexed fiber ring laser, based on optical add-drop multiplexers to interconnect intensity sensors has been experimentally demonstrated. Three different laser lines were obtained simultaneously all with an optical signal to noise ratio higher than 30dB. This proposed configuration is based on commercial devices and is adapted to the ITU channels normative. By using this configuration each sensor was associated with a different wavelength directly offered by each OADM and a reference wavelength was also included in order to distinguish between power variations induced by the transducer or to detect a fiber failure. This sensor system has been experimentally verified by using microbending sensors obtaining experimental slope sensitivity as good as -0.327dB/µm. P78/Paper 9157-300

Acoustic fiber laser array architecture with reduced optical feedback limitations Stéphanie Molin, Thales Research and Technology France (France); Renaud Bouffaron, Martine Doisy, Thales Underwater Systems (France); Alain Mugnier, David Pureur, Quantel (France)

Many sensing applications would benefit of multiplexing a maximum number of Distributed FeedBack Fiber Lasers (DFB-FLs) on the same optical fiber. However, in such configurations, some physical mechanisms may impact DFB-FLs stable operation, limiting, for instance, the number of DFB-FLs spliced on the same fiber and the distance between them. The aim of this experimental study is to investigate the impact of optical feedback on DFB-FLs stability. The results of our study are used to propose possible associated architectures. P79/Paper 9157-308

Mitigation of polarization fading in BOTDR sensors by using optical pulses with orthogonal polarizations Yulong Cao, Shanghai Institute of Optics and Fine Mechanics (China), Univ. of Chinese Academy of Sciences (China); Qing Ye, Zhengqing Pan, Haiwen Cai, Ronghui Qu, Zujie Fang, Shanghai Institute of Optics and Fine Mechanics (China); Hao Zhao, Shanghai Bandweaver Technologies Co., Ltd. (China), Shanghai Synet Optics Corp. (China)

Polarization fading is a phenomenon observed often in BOTDR distributed sensors, which greatly reduces signal-to-noise ratio of the detected signal. We proposed a scheme based on injecting optical pulse probes with orthogonal polarization states, which is generated by a delay Mach-Zehnder interferometer (MZI) composed of two polarization beam splitters (PBS). The principle is analyzed and the effect of reducing polarization fading is demonstrated experimentally. The method uses simple and passive components and is suitable for practical applications. P80/Paper 9157-318

Balanced detection in Brillouin optical time domain analysis Alejandro Dominguez-Lopez, Alexia Lopez-Gil, Sonia Martin-Lopez, Miguel Gonzalez-Herraez, Univ. de Alcalá (Spain)

We propose the use of balanced detection in Brillouin Optical Time Domain Analysis (BOTDA) sensors. Balanced detection can be effectively accomplishedong the Stokes and anti-Stokes bands in the probe signal. This type of detection leads to a doubling of the traceplitude and at least a sqrt(2) increase in signal to noise ratio over the conventional configuration. Moreover, it leads to a complete cancellation of the common-mode noise in the probe signal, including relative intensity noise in Raman-assisted configurations. We show all these benefits both theoretically and experimentally. P81/Paper 9157-334

Fiber optical sensor system for shape and haptics for flexible instruments in minimally invasive surgery: overview and status quo Christoph Ledermann, Hendrikje Pauer, Heinz Woern, Karlsruher Institut für Technologie (Germany)

In minimally invasive surgery, flexible mechatronic instruments promise to improve the overall performance of surgical interventions. However, those instruments require highly developed sensors in order to provide haptic feedback to the surgeon or to enable (semi-)autonomous tasks. Precisely, haptic sensors and a shape sensor are required. In this paper, we present our fiber optical sensor system of Fiber Bragg Gratings, which consists of a shape sensor, a kinesthetic sensor and a tactile sensor. The status quo of each of the three sensors is described, as well as the concept to integrate them into one fiber optical sensor system. P82/Paper 9157-336

Fading statistics in Rayleigh interferometric fiber sensors Gregory H. Ames, Walter R. Donat, Naval Undersea Warfare Ctr. (United States)

Distributed, interferometric, fiber optic sensors based on Rayleigh scattering suffer from random signal level variation (Rayleigh fading). This speckle-like phenomenon is due to the large number of scatterers. Knowledge of the statistical distribution of fading is important to estimate system performance, the likelihood of fading, and to devise strategies to mitigate fading. The distribution has been variously thought to be an exponential or Rayleigh distribution. Modeling shows the fading for the common interrogation schemes that do not use a fixed reference path to be better represented by a Gamma distribution. Laboratory measurements confirm the Gamma-like fading distribution. P83/Paper 9157-337

Advanced hybrid BOFDA/FBG sensor system for simultaneously point-wise and distributed temperature/strain measurements Syed Farhan Haider Zaidi, Scuola Superiore Sant'Anna (Italy); Katerina Krebber, Bundesanstalt für Materialforschung und -prüfung (Germany)

We propose and experimentally demonstrate for the first time to the best of our knowledge the feasibility of an integrated hybrid optical fiber sensing system that efficiently combines distributed Brillouin optical frequency-domain analysis (BOFDA) technique with FBG-based quasi-distributed approach offering the possibility for simultaneous distributed and point-wise measurements. The highly integrated proposed scheme employs Gaussian shaped, broadband and low reflectivity apodized FBGs with a common narrow-band optical source & shared receiving unit over the same sensing fiber. A single mode optical fiber is used for distributed sensing and a pair of FBGs is employed for simultaneous point-wise measurements. P84/Paper 9157-340

Synthesis of virtual Brillouin frequency shift profiles in BOTDA sensors using optical source dithering Javier Urricelqui, Mikel Sagues, Alayn Loayssa, Univ. Pública de Navarra (Spain)

We demonstrate a novel concept for Brillouin optical time domain analysis sensors that is based on synthesizing a virtual Brillouin frequency shift profile along the sensing fiber. The technique is based on modulating the wavelength of the optical source with a periodic waveform that is synchronized to the pump pulse. Application of this new tool to the compensation of non-local effects and Brillouin-induced noise in distributed sensors is experimentally demonstrated. P85/Paper 9157-341

Polarization diversity for Brillouin distributed fiber sensors based on a double orthogonal pump Javier Urricelqui, Felipe López-Fernandino, Mikel Sagues, Alayn Loayssa, Univ. Pública de Navarra (Spain)

We demonstrate a novel Brillouin optical time domain analysis sensor deploying a polarization diversity technique which eliminates the need for polarization scrambling, providing measurements that are largely immune to the state of polarization of the probe wave and the pump pulses throughout the sensing fiber. This can be exploited to reduce the measurement time or can lead to an enhanced precision. Proof of concept experiments demonstrate a 651 Hz sampling rate with 1m resolution over a 930m sensing fiber. P86/Paper 9157-180

Dual-environment pressure sensor using a photonic-crystal fiber Jonas H. Osório, Juliano G. Hayashi, Yovanny A. V. Espinel, Univ. Estadual de Campinas (Brazil); Marcos A. R. Franco, Instituto de Estudos Avançados (Brazil); Miguel V. Andrés, Univ. de València (Spain); Cristiano M. B. Cordeiro, Univ. Estadual de Campinas (Brazil)

In this paper, we report the development of a side-hole photonic-crystal fiber (SH-PCF) based dual-environment pressure sensor. SH-PCF sensitivity to pressure variations was measured and compared to simulated data. SH-PCF sensitivity was found to be 2.8 times higher than the one presented by the commercial PM-1550-01 fiber. For probing two environments, one spliced two sections of the studied SH-PCF with different lengths in a solc-filter-like configuration. Individual responses of the first and second fiber can be independently obtained in this setup. Therefore, making use of SH-PCF sensitivity to pressure variations, a pressure sensor for dual environment monitoring is build up. P87/Paper 9157-347

Distributed audio recording using OFDR with double interrogation Haniel Gabai, Avishay Eyal, Tel Aviv Univ. (Israel)

We introduce a phase sensitive, dynamic and long range fiber-optic sensing system with fully distributed audio recording capabilities. The proposed system implements a recently developed OFDR design, which is based on double interrogation of a sensing fiber with equally-spaced discrete reflectors. In this paper, the ability of each sensing segment to operate as an independent, purely optical audio recorder with little cross-talk artifacts is demonstrated. P88/Paper 9157-352

Optimized four-section-bright-pulse distributed Brillouin sensor with high spatial resolution Zhisheng Yang, xiaobin hong, Hongxiang Guo, Jian Wu, jintong lin, Beijing Univ. of Posts and Telecommunications (China)

We propose and demonstrate a Brillouin distributed fiber sensor with high spatial resolution using four-section-bright-pulse, in which the second section of the pump pulse acts as sensing pulse, while the third section is used to compensate the second echo. A general analytical model of this kind of technique is presented, which provides a full physical insight into the Brillouin interaction occurring in this configuration. A computing method to optimize the parameters in the system is also given. This simple but useful proposal is experimentally validated that can distinguish the short section with small temperature/strain change. P89/Paper 9157-367

Detection of local birefringence in embedded fiber Bragg grating caused by concentrated transverse load using optical frequency domain reflectometry Daichi Wada, Hideaki Murayama, The Univ. of Tokyo (Japan); Hirotaka Igawa, Japan Aerospace Exploration Agency (Japan)

We investigate the capability of local birefringence detection in an embedded fiber Bragg grating (FBG) using optical frequency domain reflectometry. We embed an FBG into carbon fiber reinforced plastic specimen, and conduct 3-point bending test. The cross-sectional stresses are applied to the FBG at the loading location in addition to the non-uniform longitudinal strain distribution over the length of the FBG. The local birefringence due to the cross-sectional stresses was successfully detected while the non-uniform longitudinal strain distribution was accurately measured. P90/Paper 9157-373

End-reflection assisted time domain Brillouin sensing with a novel probe pulse arrangement for branched fiber Chihiro Kito, Fumihiko Ito, NTT Access Network Service Systems Labs. (Japan); Hiroshi Takahashi, NTT Photonics Labs. (Japan); Kunihiro Toge, NTT Access Network Service Systems Labs. (Japan)

We present a novel Brillouin time domain analysis configuration for monitoring parallel fiber networks. By employing branch length manipulation, the new probe pulse arrangement improves the system dynamic range compared with a previously reported approach that uses a single pair of pump and probe pulses. This technique is promising in parallel fiber sensing that enhances the system reliability. P91/Paper 9157-384

Brillouin Optical Correlation Domain Reflectometry with Double Frequency Modulation and Phase Modulation Ora Matsuoka, Masato Kishi, Kazuo Hotate, The Univ. of Tokyo (Japan)

We propose and experimentally demonstrate a Brillouin optical correlation domain reflectometry system with double frequency modulation and phase modulation. Double frequency modulation onto the laser is used for expanding the measurement range, and phase modulation onto the reference lightwave is used for reducing background noise to enhance resolution and strain dynamic range. A section with 15 cm length and 7000 micro-strain was detected in 1250 m single mode fiber with 5.2 cm nominal spatial resolution.

P92/Paper 9157-398

Effect of laser linewidth on phase-OTDR based distributed vibration sensing regime Leilei Shi, Tao Zhu, Qian He, Shihong Huang, Chongqing Univ. (China)

The effect of fiber laser linewidth on the optical time-domain reflectometer based vibration distributed sensing regime is studied experimentally in this paper. Lasers with multi-longitudinal modes, 5 kHz and ~800 Hz linewidth single longitudinal mode are interrogated as light source successively. Experiments show that narrower linewidth laser results in higher repeatable and stable scattering spectrum. When the 800 Hz linewidth laser is modulated into 50 ns width pulses, the signal to noise ratio is ~ 6 dB and the spatial resolution is improved to 3 m, breaking the traditional theory limit. P93/Paper 9157-407

Simplified Brillouin optical time-domain analysis with extended measurement range by frequency dithering Jun Gi Hong, Kwang Yong Song, Chung-Ang Univ. (Korea, Republic of)

We demonstrate a simplified Brillouin optical-time domain analysis system based on direct current modulation of a laser diode with an extended measurement range and an enhanced spatial resolution. Slow and periodic frequency dithering is additionally applied to the laser diode to suppress the noise originated from coherent Rayleigh scattering. The distribution of Brillouin gain spectra along a 25 km fiber is successfully measured with a 1 m spatial resolution and an accuracy of standard deviation of 0.78 MHz, confirming its high practicality as a cost-effective solution. P94/Paper 9157-420

High spatial resolution OFDR based on broadened optical frequency sweeping by four-wave-mixing Dan Xu, Jiangbing Du, Xinyu Fan, Qingwen Liu, Zuyuan He, Shanghai Jiao Tong Univ. (China)

We demonstrate a method for high spatial resolution optical frequency domain reflectometry (OFDR) by utilizing degenerated four-wave-mixing (FWM) for broadening the frequency sweeping. High order sideband is obtained from an optical comb and is consequently utilized as the pump for the FWM. An idler wavelength is produced after the FWM and 21-times broadened optical frequency sweeping is achieved compared with the radio frequency (RF) sweeping. 0.75-cm spatial resolution is obtained with RF frequency sweeping span of 638.4 MHz. P95/Paper 9157-432

Comparison of the use of first and second-order Ramanplification to assist a phase-sensitive optical time domain reflectometer in distributed vibration sensing over 125 km Hugo F. Martins, INESC TEC (Portugal), Univ. do Porto (Portugal), Univ. de Alcalá (Spain); Sonia Martin-Lopez, Massimo L. Filograno, Univ. de Alcalá (Spain); Pedro Corredera, Instituto de Óptica, CSIC (Spain); Orlando Frazão, INESC TEC (Portugal), Univ. do Porto (Portugal); Miguel González-Herráez, Univ. de Alcalá (Spain)

We report on the use of second-order Ramanplification to assist a phase-sensitive optical time domain reflectometer (ϕOTDR) used for vibration measurements over very long distances. The sensor was able to measure vibrations of up to 380 Hz (limit set by the time of flight of light pulses) in a distance of 125 km with a resolution of 10 m and no post-processing. Balanced detection is used to reduce the relative intensity noise. A comparison with a sensor using first-order Ramanplification under similar conditions is presented and a clear improvement of performance is demonstrated. P96/Paper 9157-459

Cavity and random ultralong lasers in BOTDAplification Javier Nuño, Juan D. Ania-Castañón, Instituto de Óptica, CSIC (Spain)

The predicted performance of BOTDA sensors assisted by Ramanplification provided through either cavity or laterally-pumped mirrorless random ultralong laser schemes is compared, showing that although the latter are less affected by RIN transfer for sensing lengths above 100 km, they also require much higher pump powers and suffer more from SPM-induced broadening of the pulsed Brillouin pump. P97/Paper 9157-466

Effect of pump-read optical path difference on the measurement of Brillouin dynamic grating spectra localized by the correlation domain technique with a single laser setup Rodrigo K. Yamashita, Masato Kishi, Kazuo Hotate, The Univ. of Tokyo (Japan)

In correlation domain distributed measurement of Brillouin dynamic grating (BDG) in polarization maintaining fiber, adjustment of the frequency modulation (FM) phase between the pump and read lightwaves is essential. We experimentally evaluated the phase

difference impact on the measurement. A single laser setup can acquire the BDG spectra with higher stability, but the FM phase relation is fixed. Therefore the FM synchronization is not guaranteed for all points of the fiber under test due to the birefringence of the fiber. In this report, we varied the optical path difference between the pump and the read lightwaves, showing the spectrum degradation. P98/Paper 9157-476

Distributed temperature monitoring for liquid sodium leakage detection using OFDR-based Rayleigh backscattering Ekaterina Boldyreva, Romain Cotillard, Gillaume Laffont, Pierre G. Ferdinand, Denis Cambet, Jean-Philippe Jeannot, Pierre Charvet, Serge Albadéjo, Gilles Rodriguez, Commissariat à l'Énergie Atomique (France)

For the first time, a gold coated single mode optical fiber has been used to detect a liquid sodium leakage on a pipe of secondary circuit pipe mock-up of nuclear fast reactor (Gen IV) by means of Optical Frequency Domain Reflectometry-based on Rayleigh backscattering. During 150 min of the experiment we were able to detect and monitor the evolution of a liquid sodium leakage on the surface of the pipe. P99/Paper 9157-463

Fully switchable multi-wavelength fiber laser based interrogator system for remote and versatile fiber optic sensors multiplexing structures Mikel Bravo Acha, Veronica DeMiguel-Soto, Amaia Ortigosa, Manuel Lopez-Amo, Univ. Pública de Navarra (Spain)

A novel interrogation system for multiple fiber optic sensor technologies and based on a fully-switchable multi-wavelength fiber laser (MWFL) is proposed and experimentally demonstrated. The MWFL can generate any wavelength combination with a minimum emission line distance up to 50 GHz fitting the ITU grid specifications. On the other hand, as proof of concept sensor network, two different networks were multiplexed by using a remote powered by light fiber optic switch. They are based on two different sensor technologies. One of them based on PCF intensity sensors and multiplexed by using an 8 port WDM and the other one based on wavelength temperature/strain FBG sensors. P100/Paper 9157-531

Extending the sensing range of Brillouin optical time-domain analysis up to 325 km combining four optical repeaters Flavien Gyger, Etienne Rochat, Sanghoon Chin, Marc Niklès, Omnisens SA (Switzerland)

A novel scheme is proposed to extend the sensing range of Brillouin optical time-domain analyzers (BOTDA). Specially-designed erbium doped fiberplifier (EDFA) repeaters are located every 65km fiber along the sensing cable to achieve a total sensing length of 325km, corresponding to a 650km loop. At the end of the sensing fibre, we experimentally demonstrated a measurement repeatability of 2°C (2sigma) using a three meters spatial resolution. P101/Paper 9157-542

Characterization of fast acoustic wave propagation using OFDR with double interrogation and frequency tracking Haniel Gabai, Avishay Eyal, Tel Aviv Univ. (Israel)

A highly sensitive OFDR system capable of detecting and tracking fast acoustic wave propagation is described. The system was tested by dropping a screw (50gr) and a paperclip (<5gr) at one end of an 18m PVC pipe. The sensing fiber detected the wave propagation (v ≈ 1750m/s) along the entire pipe. Fast phase variations due to the impact of the screw led to a transient shift in the frequency of the interrogating light which corrupted the observed response. By tracking the beat frequencies of predefined reflectors and extracting theirplitudes significant improvement in the system's output was obtained. P102/Paper 9157-557

Simultaneous vibration and quasi-distributed strain measurement using incoherent OFDR and extrinsic Fabry-Perot interferometers Milan Steffen, Bundesanstalt für Materialforschung und -prüfung (Germany); Sascha Liehr, Bundesanstalt für Materialforschung und -prüfung (Germany), Aston Univ. (); Katerina Krebber, Frank Basedau, Bundesanstalt für Materialforschung und -prüfung (Germany)

We present a measurement setup for combined quasi-distributed strain and dynamic point-wise vibration measurement using an incoherent optical frequency domain reflectometry (I-OFDR) setup in combination with extrinsic Fabry-Perot interferometers (EFPIs). Several EFPIs can be multiplexed and at the same time the strain along their supply fibres can be measured in a quasi-distributed manner. The setup is characterised and a demonstration of its general performance is given. P103/Paper 9157-561

Fractional Fourier transform reflectometry Lihi A. Shiloh, Avishay Eyal, Tel Aviv Univ. (Israel)

In some OFDR implementations it is advantageous to use sinusoidal frequency tuning and to work in the linear range of the sinusoid. For a given scan frequency this limits the maximum length of the interrogated fiber. We propose a new method which allows

exceedingly large delays while maintaining high scan rates. It is based on the observation that delay of half the scan period yields linearly frequency modulated (LFM) signals at the OFDR receiver. Using Fractional Fourier Transform (FrFT) for processing the raw data enables measurement of the z-dependent reflection at long ranges with high resolution and high scan rates. P104/Paper 9157-567

Hydrogen and radiation induced effects on performances of Raman fiber-based temperature sensors Chiara Cangialosi, Youcef Ouerdane, Sylvain Girard, Aziz Boukenter, Lab. Hubert Curien (France); Marco Cannas, Univ. degli Studi di Palermo (Italy); Sylvie Delepine-Lesoille, ANDRA (France); Philippe Paillet, CEA, DAM, DIF (France)

Raman Distributed Temperature Sensors (RDTS) offer exceptional advantages for the monitoring of the envisioned French deep geological repository for nuclear wastes, called Cigéo. Here, we present experimental studies on how the performances of RDTS

-rays. Both of them are shown to strongly affect the temperature measurements made with RDTS. We showed that by adapting the characteristics of the used fiber for the sensing, we could limit its degradation but that additional hardening by system studies will have to be developed before integration of RDTS in Cigéo. P105/Paper 9157-571

Brillouin optical frequency domain analysis in polymer optical fiber Aldo Minardo, Seconda Univ degli Studi di Napoli (Italy); Romeo Bernini, CNR-IREA (Italy); Zeni Luigi, Seconda Univ. degli Studi di Napoli (Italy)

We report distributed temperature measurements in a perfluorinated graded-index polymer optical fiber (POF) with 50 µm core diameter, carried out by stimulated Brillouin scattering. Brillouin optical frequency-domain analysis (BOFDA) has been performed to extract the temperature profile along a 20-m POF fiber sample, at a nominal spatial resolution of 4 m. The results indicate that POFs are potentially useful for distributed temperature measurements based on stimulated Brillouin scattering. P106/Paper 9157-601

Novel technique for distributed fibre sensing based on faint long gratings (FLOGs) Luc Thévenaz, Sanghoon Chin, Ecole Polytechnique Fédérale de Lausanne (Switzerland); Juan Sancho, Salvador Sales, Univ. Politécnica de València (Spain)

A novel approach for fibre distributed sensing is proposed, conceived to match as closely as possible to an ideally responding distributed sensor. It is demonstrated that it can be actually realized using fibre Bragg gratings of extremely low index contrast and continuously printed over the entire fibre length. The concept is experimentally validated over a restricted distance range that proves the huge potentialities of the technique in terms of response and precision. P107/Paper 9157-635

High sampling rate multi-pulse phase-sensitive OTDR employing frequency division multiplexing Zhengqing Pan, Zhaoyong Wang, Qing Ye, Haiwen Cai, Ronghui Qu, Zujie Fang, Shanghai Institute of Optics and Fine Mechanics (China)

A novel high sampling rate multi-pulse phase-sensitive OTDR employing frequency division multiplexing (FDM) is proposed to increase the sampling rate of the long distance sensor system. Compared with the conventional phase-sensitive OTDR, the new system owns much higher detection bandwidth as more probe pulses are allowed simultaneously traveling in the sensing fiber. The feasibility of the technique is experimentally verified. By multiplexing four different frequencies, we realize a experimental system with 20kHz vibration detection bandwidth over 10km sensing range. P108/Paper 9157-639

Fast distributed temperature sensing using Brillouin beat spectrum of large effective area fiber (LEAF) Shahna M. Haneef, Prasanth P. P, Bhargav Somepalli, Deepa Venkitesh, Balaji Srinivasan, Indian Institute of Technology Madras (India)

We investigate the temperature dependence of the beat spectra of stimulated Brillouin scattering from a large effective area fiber (LEAF) in an Optical Time Domain Reflectometry (OTDR) configuration. The multiple gain peaks inherent to the design of this fiber undergo homodyning at the receiver and theplitude of one of the beat tones is monitored as a function of temperature for a 4 km long fiber. Contrary to previous reports, the beat signal of the first two peaks is found to be decreasing with temperature. The above measurement is performed within 4 ms, thus opening the possibility of dynamic measurement of temperature or strain. P109/Paper 9157-654

Distributed detection and localization of multiple dynamic perturbations using coherent correlation OTDR Mikhail G. Shlyagin, Luis Antonio Arias Castro, Ctr. de Investigación Científica y de Educación Superior de Ensenada (Mexico); Rodolfo Martinez Manuel, Univ. of Johannesburg (South Africa)

A novel technique for distributed disturbance sensor is presented. It is based on Coherent Correlation OTDR operating in CW regime. The sensor utilizes a standard telecom CW DFB diode laser as a light source and a very simple configuration. Probe signals were generated by interferometer with OPD exceeding the coherence length of the laser light. Speckle-like OTDR traces were obtained by

calculating cross-correlation function between the probe light intensity signal and the signal returned back from the sensing fiber. Perturbations are detected as time variation of correlationplitude at disturbance locations. Preliminary experiments proved operability of the sensor.

Thursday 5 June

Plenary Presentation III Thursday 5 June 2014 8:30 AM - 9:30 AM Chair: Jose Luis Santos, INESC, Porto (Portugal)

Quantum technologies for optical sensing, metrology and imaging (invited) Jonathan P. Dowling, Lousiana State Univ. (United States)

Over the past 20 years bright sources of entangled photons have led to a renaissance in quantum optical interferometry. These photon sources have been used to test the foundations of quantum mechanics and implement some of the spooky ideas associated with quantum entanglement such as quantum teleportation, quantum cryptography, quantum lithography, quantum computing logic gates, and sub-shot-noise optical interferometers. I will discuss some of these advances and the unification of optical quantum imaging, metrology, and sensing via the common language of quantum optical information processing. In particular I will discuss ways to exploit quantum optical entanglement to beat the Rayleigh diffraction limit in imaging systems such as in microscopes, LIDAR, and optical lithography. I will also discuss how this entanglement can be used to beat the shotnoise limit, for example in fiber optical gyroscopes, as well as to the sensing of biological or chemical targets.

Session 8: Distributed and Micro-Nano-structured Fiber Sensors Thursday 5 June 2014 9:30 AM - 10:30 AM

Session Chairs: Miguel González-Herráez, Univ. de Alcalá (Spain); Zuyuan He, Shanghai Jiao Tong Univ. (China)

Time: 9:30 - 9:45, Paper 9157-313

Brillouin dynamic grating time-domain slope-assisted fast and distributed strain sensing Arik Bergman, Lior Yaron, Tomi Langer, Moshe Tur, Tel Aviv Univ. (Israel)

A new fast and distributed optical time-domain sensing technique, employing the slope of Brillouin dynamic gratings (BDG) in polarization-maintaining (PM) fibers, is proposed and demonstrated. The strain sensitivity of the reflectivity of a pulsed probe, orthogonally polarized to the pumps which generated the BDG, is shown to depend on both pump and probe detuning. An optimum detuning point is then found, which provides maximum strain sensitivity. We report the measurement of 400Hz strain vibrations with a spatial resolution of 4.2cm at a sampling rate of 16kHz.

Time: 9:45 - 10:00; Paper 9157-462

Mapping the refractive index changes along Yb-doped fibers pumped at 976 nm based on acousto-optic interaction Erica P. Alcusa-Sáez, Antonio Díez, Miguel V. Andrés, Univ. de València (Spain)

In-fiber acousto-optic interaction is used to investigate the refractive index changes generated along an Yb-doped fiber by a 976 nm pump. The transmission notch created by the acoustic-induced coupling between the core mode and a cladding mode shifts to longer wavelengths when the pump is delivered to the fiber. Thermal and electronic contributions of the refractive index change are analyzed from the wavelength shift. Additionally, the non-uniform distribution of pump absorption along the fiber length is investigated by a time-resolved acousto-optic technique.

Time: 10:00 - 10:15; Paper 9157-472

Source-induced noise in stimulated Brillouin scattering Omer Shlomovits, Tomi Langer, Moshe Tur, Tel Aviv Univ. (Israel)

The performance of systems employing Stimulated Brillouin Scattering may suffer from laser phase noise affecting the coherency of the Brillouin interaction. It is numerically demonstrated how, when using two lasers setup, Brillouin gain characteristics changes depending on pump and probe temporal coherence and on Brillouin interaction length. Corresponding experimental results are also presented.

Time: 10:15 - 10:30; Paper 9157-227

A novel refractive index sensor based on an induced micro-structure fiber Guei R. Lin, Mohamad D. Baiad, Mathieu Gagne, Polytechnique Montréal (Canada); Wen-Fung Liu, Feng-Chia Univ. (Taiwan); Raman Kashyap, Polytechnique Montréal (Canada)

We demonstrate the first application of a refractive index sensor based on the micro-structure induced by the fiber fuse. This simple in-line sensor fabricated with standard optical fibers has the potential for low-cost mass production, and therefore be used as a disposable device.

Coffee Break 10:30 AM - 11:00 AM

Session 9: Micro-structured and Laser Postprocesed Fiber Sensors Thursday 5 June 2014 11:00 AM - 12:30 PM Session Chairs: Wei Jin, The Hong Kong Polytechnic Univ. (Hong Kong, China) Leszek R. Jaroszewicz, Military University of Technology (Poland) Time: 11:00 - 11:30; Invited Paper 9157-680

Hybrid fibers: a base for creating new sensing fibers Markus A. Schmidt, Friedrich-Schiller-Univ. Jena (Germany)

Hybrid optical fibers are fiber type waveguides including multimaterial large aspect ratio nano and microstructures. Using our pressure assisted melt filling approach various hybrid waveguides have been fabricated inside photonic crystal fibers by filling the air holes with materials such as noble metals, semiconductors, fluids or low‐melting compound glasses. In this talk I will review our latest results on fiber based plasmonics and nonlinear optics. Time: 11:30 - 11:45; Paper 9157-275

Bend-insensitive fiber based vibration sensor Yanping Xu, Ping Lu, Farhana Baset, Vedula Ravi Bhardwaj, Xiaoyi Bao, Univ. of Ottawa (Canada)

We report two novel fiber-optic vibration sensors based on standard telecom bend-insensitive fiber (BIF). A tapered BIF forming a fiber Mach-Zehnder interferometer could measure continuous and damped vibration from 1 Hz up to 500 kHz. An enclosed microcantilever is fabricated inside the BIF by chemical etching and fusion spliced with a readout single-mode fiber that exhibits a frequency range from 5 Hz to 10 kHz with high signal-to-noise ratio (SNR) up to 68 dB. The unique double cladding structure of the BIF ensures both sensors with advantages of compactness, high resistance to the external disturbance and stronger mechanical strength. Time: 11:45 - 12:00; Paper 9157-335

Highly birefringent suspended core photonic microcells for sensing applications Chao Wang, Wei Jin, Wa Jin, Jun Ma, Hoi Lut Ho, The Hong Kong Polytechnic Univ. (China)

We report a novel type of highly birefringent suspended core (SC) photonic microcells made by selectively inflating four air-columns in a solid core photonic crystal fiber. The wavelength-scale SC has two-fold rotational symmetry and exhibits high phase and group birefringence of ~3 x10^-3 and ~5 x10^-3 respectively at 1550 nm. By incorporating such microcells into Sagnac fiber loop interferometers, we demonstrated refractive index, temperature and gas pressure sensors with good performances. Time: 12:00 - 12:15; Paper 9157-343

Microstructured optical fiber Bragg grating-based strain and temperature sensing in the concrete buffer of the Belgian supercontainer concept Thomas Geernaert, Sanne Sulejmani, Camille Sonnenfeld, Vrije Univ. Brussel (Belgium); Geert Luyckx, Univ. Gent (Belgium); Karima Chah, Univ. de Mons (Belgium); Lou Areias, EIG EURIDICE (Belgium), Vrije Univ. Brussel (Belgium); Pawel Mergo, Univ. of Maria Curie-Sklodowska (Poland); Waclaw Urbanczyk, Wroclaw Univ. of Technology (Poland); Philippe Van Marcke, Erik Coppens, ONDRAF/NIRAS (Belgium); Hugo Thienpont, Francis Berghmans, Vrije Univ. Brussel (Belgium)

We present the use of microstructured optical fiber Bragg grating-based sensors for strain and temperature monitoring inside the concrete buffer of the Belgian supercontainer concept, demonstrated in a half-scale test in 2013. This test incorporated several optical fiber sensors inside the concrete buffer for production and condition monitoring. The optical fiber sensors presented here consist of small carbon-reinforced composite plates in which highly birefringent photonic crystal fibers, equipped with fiber Bragg gratings, were embedded. The double reflection spectrum of these MOFGBs allows to simultaneously monitoring strain and temperature, as confirmed by comparison with data coming from thermocouples and vibrating-wire sensors. Time: 12:15 - 12:30; Paper 9157-396

Tunable phase-shifted FBG based on an in-grating bubble Changrui Liao, Shenzhen Univ. (China); Lei Xu, Shenzhen Institute of Information Technology (China); Yiping Wang, Shenzhen Univ. (China); D. N. Wang, The Hong Kong Polytechnic Univ. (Hong Kong, China); Qiao Wang, Zhengyong Li, Xiaoyong Zhong, Jiangtao Zhou, Yingjie Liu, Shenzhen Univ. (China)

We present a new type of phase-shifted FBGs based on an in-grating bubble fabricated by femtosecond laser ablation together with fusion splicing technique. A micro-channel vertically crossing the bubble is drilled by femtosecond laser to allow liquid to flow in or

out. By filling different refractive index liquid into the bubble, the phase-shift peak is found to experience a linear red shift with the increase of refractive index. Such a PS-FBG could be used to develop a promising tunable optical filter and sensor.

Lunch Break 12:30 PM - 2:00 PM

Session 10: Sensor Application and Field Tests I Thursday 5 June 2014 2:00 PM - 3:30 PM

Session Chairs: Hypolito J. Kalinowski, Univ. Tecnológica Federal do Paraná (Brazil); Pierre G. Ferdinand, Commissariat à l'Énergie Atomique (France)

Time: 14:00 - 14:30; Invited Paper 9157-681

Precise sensing utilizing optical fiber for space craft Tadahito Mizutani, Japan Aerospace Exploration Agency (Japan)

The ultimate performance of the spacecraft is based on the strict structural requirement with the high accuracy and the high stability though they are operated under the severe space environment. Fiber optic sensors are one of the promising sensors for the precise measurement and utilizing for some R&D activities of the space engineering in Japan Aerospace Exploration Agency. Time: 14:30 - 14:45; Paper 9157-258

Field test for real-time position and speed monitoring of trains using phase-sensitive optical time domain reflectometry (Φ-OTDR) Ning Duan, Fei Peng, Yunjiang Rao, Jiang Du, Yao Lin, Univ. of Electronic Science and Technology of China (China)

It is essential to carry out real-time position and speed of trains to ensure the safety of railway operation. In this paper, the phase-sensitive optical-time-domain reflectometry (Φ-OTDR) is proposed and demonstrated to overcome the disadvantage of the track circuit that is currently used and has the risk to be damaged by lightening, for the first time, to the best of our knowledge. A long sensing cable, buried nearby two parallel railways, is used to detect the vibration signals generated by trains with Φ-OTDR and the real vibration signals of the trains are extracted/quantified utilizing wavelet denoising. With the wavelet edge detection, the operation status of two nearby trains, including their relative position and speed, are obtained over a 10.2 km measurement length in real-time. This work offers a new passive way for safety monitoring of railway operation. Time: 14:45 - 15:00; Paper 9157-323

Glue-induced birefringence in surface-attached FBG strain sensors Dominik Helminger, Alexej Daitche, Johannes Roths, Munich Univ. of Applied Sciences (Germany)

The influence of the gluing process on the birefringence of surface-glued FBGs that were inscribed in highly birefringence (HiBi) optical fibers of type Panda was studied by monitoring the variation of the birefringence during the gluing procedure. Based on this results, it can be estimated that for conventional FBGs in single mode fibers a glue-induced birefringence in the order of ΔB = 3.4 10-5 can be expected, which has to be taken into account if highly accurate strain measurements have to be achieved. Time: 15:00 - 15:15; Paper 9157-333

Birefringence upper limit analysis of low birefringence fibers employed in the Faraday effect current sensors Natasha T. Vukovic, M. Segura Sarmiento, T. May-Smith, W. Loh, M. N. Zervas, Univ. of Southampton (United Kingdom)

The theoretical model of the Faraday rotation in the low birefringence optical fiber is proposed to serve as a convenient tool for the determination of the birefringence upper limit allowed to retain current sensor sensitivity. The measurement technique offers a fast and efficient determination of the ultra-low linear birefringence when other techniques are not sensitive enough or they are difficult to implement. A temperature dependence of the Faraday rotation and its causes are investigated. Time: 15:15 - 15:30; Paper 9157-453

Signal-to-noise ratio evaluation with draw tower fibre Bragg gratings (DTGs) for dynamic strain sensing at elevated temperatures and corrosive environment Ben De Pauw, Vrije Univ. Brussel (Belgium), SCK CEN (Belgium); Alfredo Lamberti, Steve Vanlanduit, Vrije Univ. Brussel (Belgium); Katrien Van Tichelen, SCK CEN (Belgium); Thomas Geernaert, Francis Berghmans, Vrije Univ. Brussel (Belgium)

Measuring strain at the surface of a structure can help to estimate the dynamical properties of the structure under test. Such a structure can be a fuel assembly of a nuclear reactor consisting of fuel pins. In this paper we demonstrate a method to integrate draw

tower gratings (DTGs) in a fuel pin and we subject this pin to conditions close to those encountered in a heavy liquid metal (HLM) reactor. More specifically, we report on the performance of DTGs used as a strain sensor when immersed in HLM during thermal cycles (up to 300°C) for up to 700 hours.

Coffee Break 3:30 PM - 4:00 PM

Session 11: Sensor Application and Field Tests II Thursday 5 June 2014 4:00 PM - 5:00 PM

Session Chairs:

Wojtek J. Bock, Univ. du Québec en Outaouais (Canada)

Hideaki Murayama, The Univ. of Tokyo (Japan)

Time: 16:00 - 16:30; Invited Paper 9157-682

Fiber optic system for the real time detection, localization, and classification of

damage in composite aircraft structures Edgar A. Mendoza, Redondo Optics, Inc. (United States)

Acoustic emission is the leading structural health monitoring technique use for the early warning detection of structural damage in advanced composite structures associated with impacts, cracks, fracture, and delaminations. This paper describes progress towards the development of a fiber optic acoustic emission sensor (FAESense™) system based on the use of a novel two-wave mixing interferometer produced on a photonic integrated circuit (PIC) microchip. Time: 16:30 - 16:45; Paper 9157-497

Regeneration experiments with fibre Bragg gratings in hydrogen out-diffused fibres Leonhard Polz, Andreas Dörfler, Munich Univ. of Applied Sciences (Germany); Hartmut Bartelt, Institut für Photonische Technologien e.V. (Germany); Johannes Roths, Munich Univ. of Applied Sciences (Germany)

The regeneration of fibre Bragg gratings (FBG) is supposed to be seeded by the relief of the in-frozen core cladding stress of the fibre. Earlier results lead to the assumption that the diffusion process of small atoms or molecules through the glass matrix is sufficient to seed regeneration of an FBG. To prove this theory, a regeneration experiment was performed with hydrogen loaded, pristine and out-diffused SMF28 fibers, respectively. For the FBG in an out-diffused fibre, the fibre was stored at room temperature after hydrogen loading to get rid of the totalount of hydrogen before FBG inscription. The FBG inscription experiments confirmed that the diffusion of hydrogen changes the fibre intrinsic stresses. From all three kinds of SMF28 fibers, one FBG was annealed with a stepwise temperature profile for regeneration. Only the FBG in hydrogen loaded fibre regenerated, what implies that the formation of hydroxyl groups is necessary for the regeneration process. The reduction of the in-frozen stress due to the hydrogen diffusion, in contrast, was not sufficient to seed regeneration Time: 16:45 - 17:00; Paper 9157-540

Femtosecond laser aided processing of optical sensor fibers for 3D medical navigation and tracking (FiberNavi) Christian Waltermann, Jan C. Koch, Martin Angelmahr, Wolfgang Schade, Michael Witte, Fraunhofer-Institut für Nachrichtentechnik Heinrich-Hertz-Institut (Germany); Nils Kohn, Dirk Wilhelm, Armin Schneider, Hubertus Feußner, Technische Univ. München (Germany)

A new concept for fiber-optical 3D shape sensing applying femtosecond laser technology for high- precision direct writing of Bragg gratings within the core and the cladding of single core standard telecom fibers is presented. This new technology enables a cost-efficient and real-time 3D shape sensing and navigation of medical catheters or endoscopes only by means of passive optical sensor elements. First prototypes showed the possibility to achieve absolute navigation accuracy of four mm per meter and have successfully been tested in clinical environment.

Poster Session III (112 papers)

Thursday 5 June 2014 5:00 PM - 6:30 PM Panel or Board number 1/Paper 9157-92

Optical loading sensor based on single polarization fiber laser incorporating an intra-cavity 45º-TFG Zhongyuan Sun, Chengbo Mou, Zhijun Yan, Aston Univ. (United Kingdom); Xiangchuan Wang, Nanjing Univ. (China), Aston Univ. (United Kingdom); Lin Zhang, Aston Univ. (United Kingdom)

We have experimentally demonstrated an active loading sensor system based on a fiber ring laser with single-polarization output using an intra-cavity 45°-tilted fiber grating (45°-TFG). When the laser cavity fiber subjected to loading, the laser output is encoded with the load and can be measured and monitored by a power metre. A loading sensitivity as high as 0.033/ (kg•m-1) has been achieved using this laser. The experiment results clearly show that single polarization fiber laser may be developed to a low-cost high-sensitivity loading sensor system. P2/Paper 9157-128

Highly focused conical optical field for Pico-Newton scale force sensing Hongchang Deng, Libo Yuan, Harbin Engineering Univ. (China)

We propose a highly focused conical optical filed generated by cone-frustum-shaped annular core fiber tip for Pico-Newton scale force sensing. We show that there are stable three-dimensional trap-points for Rayleigh particles in the main lobe and every ring of such field with Bessel-like profile. And the transverse trapping forces are much greater (almost 30 times) than their corresponding longitudinal radiation forces so that a particle trapped by highly focused conical beam is only sensitive for disturbing force in longitudinal direction. Force sensitivities in longitudinal direction and the detection range are also discussed. P3/Paper 9157-144

Dual-optical-response photonic crystal fibre interferometer for multi-parameter sensing Joel Villatoro, Univ. del País Vasco (Spain), IKERBASQUE (Spain); Vladimir P. Minkovich, Ctr. de Investigaciones en Óptica A. C. (Mexico); Joseba Zubia, Univ. del País Vasco (Spain)

An all-fiber mode interferometer consisting of a short segment of photonic crystal fiber (PCF) fusion spliced to standard single mode optical fiber and pressed on localized regions is proposed for multi-parameter sensing. In our configuration, the physical parameter being sensed changes the fringe contrast (or visibility) of the interference pattern and also causes a shift to the same. To achieve this dual effect the device is pressed on localized regions over a few millimeters. In this manner we introduce losses and effective refractive index changes to the interference modes, hence visibility and shift to the interference pattern. Our interferometer is suitable for monitoring diverse physical parameters such as weight, force, pressure, load, etc. The advantage is that no temperature or power fluctuations compensation is required. P4/Paper 9157-151

Absolute strain measurement based on a microfiber Mach-Zehnder interferometer Sung-Jae Kim, Min-Seok Yoon, Sunduck Kim, Oh-Jang Kwon, Young-Geun Han, Hanyang Univ. (Korea, Republic of)

A microfiber-based Mach-Zehnder interferometer (MZI) for measurement of absolute strain is proposed and demonstrated experimentally. The diameter of the microfiber is optimized to induce the negative thermo-optic effect in the microfiber MZI and the temperature sensitivity of the microfiber MZI is successfully suppressed. When the diameter of the microfiber is ~5 um, the temperature sensitivity of the microfiber-MZI is dramatically mitigated. We apply the proposed microfiber MZI for absolute strain measurement and its strain sensitivity is measured to be ~7.13×10-2 nm/ue. P5/Paper 9157-198

Phase sensitivity of hollow-core photonic bandgap fiber to internal gas pressure Yingchun Cao, Fan Yang, Hoi Lut Ho, Wei Jin, The Hong Kong Polytechnic Univ. (Hong Kong, China)

Phase sensitivity of the fundamental mode of hollow-core photonic bandgap fiber to gas pressure applied internally to its core is investigated. The measured phase sensitivity for a 95-cm-long fiber is 9.92 rad/kPa, over two orders of magnitude higher than that to external pressure. The large phase sensitivity is attributed mainly to the pressure-induced refractive index change of air inside the fiber core. Such an effect may be exploited for high sensitivity pressure sensing and biochemical and environmental process analysis involving pressure variations. P6/Paper 9157-200

Long period gratings in highly birefringent microfibers Wa Jin, The Hong Kong Polytechnic Univ. (Hong Kong, China), The Hong Kong Polytechnic Univ. (Hong Kong, China); HangFeng Xuan, The Hong Kong Polytechnic Univ. (Hong Kong, China); Wei Jin, The Hong Kong Polytechnic Univ. (Hong Kong, China), The Hong Kong Polytechnic Univ. (Hong Kong, China)

We report the fabrication of long-period gratings (LPGs) in highly birefringent (Hi-Bi) microfibers. The LPGs were fabricated by using a femtosecond infrared laser to modify the surface or a CO2 laser to induce micro-tapers periodically along the Hi-Bi microfibers. These LPGs have pitches from tens to hundreds of micrometers and very strong polarization dependent resonances. A LPG fabricated on a Hi-Bi microfiber with a major-diameter of ~2.8 μm and an ellipticity of ~0.7 demonstrated a refractive index sensitivity of ~4623 nm/RIU in water. P7/Paper 9157-219

Characterization of a hybrid Fabry-Perot Cavity based on a four-bridge double-Y-shape-core microstructured fiber Ana M. R. Pinto, Aitor Lopez-Aldaba, Manuel Lopez-Amo, Univ. Pública de Navarra (Spain); Orlando Frazao, José Luís C. Santos, INESC Porto (Portugal); José M. Baptista, INESC Porto (Portugal), Univ. da Madeira (Portugal); Hardy Baierl, Jean-Louis Auguste, Raphaël Jamier, Philippe Roy, CNRS, XLIM Institut de Recherche (France)

In this work, a hybrid Fabry-Perot interferometer based on a novel four-bridge microstructured fiber is presented and characterized. The characterization of this cavity is performed in the L-band using two different instruments: an optical spectrum analyzer and an optical backscatter reflectometer. The Fabry-Perot output signal presents linear variation with temperature changes (sensitivity 9.8-11.9 pm/ºC), variation with the polarization states of light and high stability. P8/Paper 9157-221

Microstructured optical fiber Bragg grating-based shear stress sensing in adhesive bonds Sanne Sulejmani, Camille Sonnenfeld, Thomas Geernaert, Vrije Univ. Brussel (Belgium); Geert Luyckx, Univ. Gent (Belgium); Danny Van Hemelrijck, Vrije Univ. Brussel (Belgium); Pawel Mergo, Krzysztof Skorupski, Univ. of Maria Curie-Sklodowska (Poland); Waclaw Urbanczyk, Wroclaw Univ. of Technology (Poland); Karima Chah, Univ. de Mons (Belgium); Francis Berghmans, Hugo Thienpont, Vrije Univ. Brussel (Belgium)

We present shear stress sensing with a Bragg grating sensor fabricated in a highly birefringent microstructured optical fiber. This sensor has a shear strain sensing resolution of 0.04 pm/µε when embedded in a shear loaded adhesive bond. We achieve discrete shear stress mapping in an adhesive bond by embedding a multitude of these sensors at different locations in the bond line. Experiments and numerical modeling show the limited influence of angular misalignment of the sensor on its shear stress response. Finally, we discuss the cross-sensitivity of this sensor to shear strain and temperature. P9/Paper 9157-231

All-fiber loading sensor based on 45° and 81° tilted fiber gratings Zhongyuan Sun, Zhijun Yan, Chengbo Mou, Aston Univ. (United Kingdom); Xiangchuan Wang, Nanjing Univ. (China), Aston Univ. (United Kingdom); Jianfeng Li, Univ. of Electronic Science and Technology of China (China), Aston Univ. (United Kingdom); Lin Zhang, Aston Univ. (United Kingdom)

We experimentally demonstrated an all fiber loading sensor system based on a 45°- and an 81°-tilted fiber grating (TFG). We have fabricated TFGs with tilted structures at 45° and 81° consecutively in one fiber. When the transverse load applied to the 81º-TFG, the light coupling to the two orthogonally polarized peaks will interchange from each other, which provides a solution to measure the load. We further investigated the all fiber loading sensor system using a single wavelength source and a power meter. The experimental results clearly show that a low-cost high-sensitivity loading sensor system can be developed based on the proposed TFG configuration. P10/Paper 9157-236

Hollow-core photonic bandgap fiber gas sensor with high sensitivity and fast response Fan Yang, Wei Jin, Yingchun Cao, Hoi Lut Ho, The Hong Kong Polytechnic Univ. (Hong Kong, China)

The effects of modal interference (MI) on the performance of hollow-core photonic bandgap fiber (HC-PBF) gas sensors are investigated. By optimizing mode launch, applying wavelength modulation with proper modulation parameters as well as appropriate digital signal processing, an estimated lower detection limit of <1 ppmv acetylene is achieved with 13-m long HC-PBF. The impacts of drilling side-hole on the MI and response time are also studied. With a 62-cm long sensing HC-PBF drilled with multiple side-holes, an acetylene sensor with a lower detection limit of 11 ppmv and a recovery time of 2 minute is demonstrated. P11/Paper 9157-240

Sensitivity improvements of exposed-core microstructured optical fibre Bragg grating refractive index sensors Stephen C. Warren-Smith, Tanya M. Monro, The Univ. of Adelaide (Australia)

Femtosecond laser written Bragg gratings have been written in various exposed-core microstructured optical fibres (EC-MOFs) for the first time. The EC-MOFs have different core diameters ranging from 2.7 µm to 12.5 µm and offer different degrees of core access depending on application requirements. Writing a Bragg grating on an open core fibre allows for refractive index based sensing, with a view to multiplexed biosensing. Smaller core fibres are shown both experimentally and theoretically to provide a higher sensitivity, with experimental sensitivities demonstrated up to 6.4 nm/RIU over the refractive index range from 1.333 (water) to 1.377 (isopropanol). P12/Paper 9157-249

Optical fiber Fabry-Pérot sensor fabrication based on focused ion beam post-processing Ricardo M. Andre, INESC Porto (Portugal), Univ. do Porto (Portugal), Leibniz Institute of Photonic Technology (Germany); Simon Pevec, Univ. of Maribor (Slovenia); Martin Becker, Jan Dellith, Manfred Rothhardt, Institut für Photonische Technologien e.V. (Germany); Manuel B. Marques, INESC Porto (Portugal), Univ. do Porto (Portugal); Denis Donlagic, Univ. of Maribor (Slovenia); Hartmut Bartelt, Institut für Photonische Technologien e.V. (Germany); Orlando Frazão, INESC Porto (Portugal), Univ. do Porto (Portugal)

A combination of focused ion beam milling and chemical etching is proposed for the creation of Fabry-Pérot cavities in microwires. Both simple cavities and cantilevers are created on 15 μm-diameter microwires and characterized in temperature. The cantilever structure shows sensitivity to vibration and is capable of measuring frequencies in the range 1 Hz – 40 kHz.

P13/Paper 9157-251

Microtips at photonic crystal fibers as functional elements for near-field scanning optical microscopy probes Paulina Pura, Military Univ. of Technology (Poland); Michal Szymanski, Military Univ. of Technology (Poland), InPhoTech Ltd. (Poland); Leszek R. Jaroszewicz, Paweł Marć, Military Univ. of Technology (Poland); Michał Dudek, Małgorzata Kujawińska, Warsaw Univ. of Technology (Poland); Marek Napierała, Tomasz Nasiłowski, Łukasz Ostrowski, Military Univ. of Technology (Poland), InPhoTech Ltd. (Poland)

We present the process of the microtip fabrication at the LMA-10 fiber designed for near-field scanning optical microscopy probes. Facilitation of manufacturing procedure as well as proper focusing conditions of such elements are the main advantages of such microelements production. P14/Paper 9157-263

D-shape optical fiber refractometer based on TM and TE Lossy Mode Resonances Pablo Zubiate, Carlos R. Zamarreño, Ignacio Del Villar, Ignacio R. Matias, Francisco J. Arregui, Univ. Pública de Navarra (Spain)

The fabrication and characterization of an optical fiber refractometer based on Lossy Mode Resonances (LMR) is presented. TiO2/ poly (sodium 4-styrenesulfonate) coatings deposited on side-polished D-shaped optical fibers are used as LMR supporting coatings. LMRs are sensitive to the external medium refractive index and D-shaped optical fibers enable the observation of TE and TM LMR polarizations. These refractometers based on TE and TM LMR showed an average sensitivity of 2737 nm/RIU and 2893 nm/RIU respectively for a surrounding medium refractive index (SMRI) range from 1.35 to 1.41. P15/Paper 9157-276

In-fiber integrated microfluidic sensor based on optical fiber with suspended core Tingting Yuan, Xinghua Yang, Harbin Engineering Univ. (China); Pingping Teng, Harbin First Machinery Manufacturing Group Co., Ltd. (China); Chunlan Liu, Entao Li, Enming Zhao, Libo Yuan, Harbin Engineering Univ. (China)

We report an in-fiber integrated chemiluminiscence sensor based on a kind of hollow optical fiber with a suspended inner core. The path of mircofluid is realized by etching microholes for inlets and outlets on the surface of the optical fiber without damaging the inner core and then constructing a melted point beside the microhole of the outlet. By injecting samples into the fiber, the liquids can be fully mixed and form steady microflows. Simultaneously, the photon emitted from the chemiluminiscence reaction is efficiently coupled into the core and can be detected at the end of the optical fiber. P16/Paper 9157-291

Improved arc discharge technique for inscribing compact long period fiber gratings Guolu Yin, Yiping Wang, Changrui Liao, Jiangtao Zhou, Xiaoyong Zhong, Shen Liu, Qiao Wang, Zhengyong Li, Bin Sun, Jun He, Guanjun Wang, Shenzhen Univ. (China)

An improved arc discharge technique was demonstrated to inscribe high-quality LPFGs with a resonant attenuation of -28 dB and an insertion loss of 0.2 dB by use of a commercial fusion splicer. Such a technique avoids the influence of the mass which is prerequisite for traditional technique. Moreover, no physical deformation was observed on the LPFG surface. Compared with more than 86 grating periods required by traditional arc discharge technique, only 27 grating periods were required to inscribe a compact LPFG by our improved arc discharge technique. P17/Paper 9157-294

Carbon-nanotube-deposited photonic crystal fiber for refractive index sensing Y. C. Tan, Z. Q. Tou, V. Mamidala, K. K. Chow, Chi Chiu Chan, Nanyang Technological Univ. (Singapore)

We present a novel fiber optic sensor based on the assembly of a thin film of carbon nanotubes (CNTs) onto a short length of photonic crystal fiber (PCF) which is spliced between two single mode fibers (SMFs). The assembly of the thin film was achieved via a simple and effective deposition method. The deposition of CNTs modified the sensing ability of the sensor, allowing it to work in the intensity encoding scheme, thus opening the sensor to the possibility of dual parameter sensing. The sensor exhibited a sensitivity of 36.1 dB/ RIU and 96.6 dB/ RIU within the ranges of 1.33-1.38 and 1.38-1.42 respectively. P18/Paper 9157-302

Magnetic field tunability of square tapered no-core fibers Yinping Miao, Jixuan Wu, Tianjin Univ. of Technology (China); Wei Lin, Nankai Univ. (China); Kailiang Zhang, Tianjin Univ. of Technology (China); Binbin Song, Hao Zhang, Bo Liu, Nankai Univ. (China)

A magnetic-field-tuned photonics device based on magnetic fluid (MF) and a square tapered no-core fiber (NCF) sandwiched between two single-mode fibers (SMFs) has been proposed. The enhanced evanescent field effect in the NCF is achieved by tapering the square NCF utilizing a fusion splicer. The spectral dependence of the proposed device on the applied magnetic-field intensity has been investigated. The results indicate that a maximal sensitivity of -18.7pm/Oe is obtained for a magnetic field strength ranging from 25Oe to 450Oe. The proposed tunable device has several advantages, including low cost, ease of fabrication, compact structure, and high sensitivity. P19/Paper 9157-306

Micro Fabry-Perot interferometer based on suspended core created by etching microstructure fiber Ruohui Wang, Xueguang Qiao, Northwest Univ. (China)

We propose a micro Fabry-Perot cavity fabricated by chemical etching a microstructure fiber. The microstructure fiber we use is an all silica endless single-mode fiber, whose core is surrounded by a group of air holes. A suspended core in the cladding can be created by removing the surrounded air hole usinghydrofluoric acid. The sensing head is fabricated by splicing a short section microstructure fiber with single mode fiber and submit the fiber end to chemical etching. The temperature sensitivity of the proposed sensor is 14.3pm/oC. P20/Paper 9157-346

A fiber tip refractive index sensor using FIB-milled gold-coated singlemode-multimode-singlemode structure Ming Ding, BeiHang Univ. (China), Univ. of Southampton (United Kingdom); Pengfei Wang, Dublin Institute of Technology (Ireland); Junlong Wang, Beijing Aerospace Times Optical-electronic Technology Co. (China); Heng Yuan, BeiHang Univ. (China); Gilberto Brambilla, Univ. of Southampton (United Kingdom)

A compact fiber tip refractive index sensor using FIB-milled gold-coated singlemode-multimode-singlemode structure is demonstrated. Focused ion beam (FIB) is exploited to cut the fiber tip to obtain a flat end-face and then a layer of gold is coated on the tip surface, to increase its reflection. An average sensitivity of 265 nm/RIU is obtained experimentally with a ~2.94 µm diameter singlemode-multimode-singlemode fiber tip (SMST). Because of several advantages, including compactness, ease of fabrication, linear response, high sensitivity, easy connection with other fiberized optical components and low cost, this refractive index sensor could find various applications in chemical and biological area. P21/Paper 9157-361

Extruded single ring hollow core optical fibers for Raman sensing Georgios Tsiminis, Kristopher J. Rowland, Heike Ebendorff-Heidepriem, The Univ. of Adelaide (Australia); Nigel A. Spooner, The Univ. of Adelaide (Australia), Defence Science and Technology Organisation (Australia); Tanya M. Monro, The Univ. of Adelaide (Australia)

In this work we report the fabrication of the first extruded hollow core optical fiber with a single ring of cladding holes. A lead-silicate glass billet is used to produce a preform through glass extrusion to create a larger-scale version of the final structure that is subsequently drawn to an optical fiber. The simple single suspended ring structure allows antiresonance reflection guiding. The resulting fibers were used to perform Raman sensing of liquid samples filling the length of the fiber, demonstrating its potential for fiber sensing applications. P22/Paper 9157-369

Microstructure-FBG hybrid load cell Rodrigo Fiorin, Faculdades Integradas do Brasil (Brazil); Larissa N. da Costa, Hilda Abe, Valmir de Oliveira, Andre Lohmann, Hypolito J. Kalinowski, Univ. Tecnológica Federal do Paraná (Brazil)

We report the fabrication of an hybrid fibre optic and T-shaped microstructrure inscribed in soda lime microscope slides by using femtosecond laser irradiation technique. that allow to construct true 3-D structures. Within the T-shaped structure a FBG was inserted and glued with photopolymer adhesive. The hybrid structure is sensitive to hydrostatic pressure. Calibration load tests were performed in the range 0 - 100 N P23/Paper 9157-370

Explosives sensing based on suspended core fiber coated with conjugated polymer Fenghong Chu, Shanghai Univ. of Electric Power (China); Georgios Tsiminis, The Univ. of Adelaide (Australia); Nigel A. Spooner, The Univ. of Adelaide (Australia), Defence Science and Technology Organisation (Australia); Tanya M. Monro, The Univ. of Adelaide (Australia)

Suspended core fibers with voids surrounding the core coated with conjugate polymer were used to detect nitroaromatic explosives based on the fluorescence quenching technique. The background Raman signal from a suspended core fiber was used as reference to optimize coupled into the core of the fiber. The fluorescence spectra were integrated across all wavelengths to extract the integrated fluorescence intensity at regular time intervals. Fluorescence decay lifetimes were obtained by fitting a single exponential decay and

were used to detect 1,4-dinitrobenzene (DNB), a member of the nitroaromatics family of explosives, in acetone solutions at concentrations as low as 6.3 ppm.

P24/Paper 9157-395

Photonic crystal fiber based modal interferometer for refractive index sensing Ming Deng, Xiaokang Sun, Wei Huang, Chongqing Univ. (China); Huifeng Wei, Jiang Li, Yangtze Optical Fiber and Cable Ltd. R&D Ctr. (China)

A core-cladding-mode interferometer (CCMI) is fabricated by splicing a single-mode fiber (SMF) to an endlessly single-mode photonic crystal fiber (ESM-PCF). The optimum collapsed length of ESM-PCF is investigated to ensure a higher-order cladding mode of ESM-PCF to be excited, serving as a sensing beam. At the end of ESM-PCF, a spherical end-facet with big radius is proposed to ensure from where the higher-order cladding mode to be reflected and then it interferes with the core mode serving as a reference beam. Such a device has an enhanced refractive index sensitivity of ~199 nm/RIU, offering potentials in biological and chemical applications. P25/Paper 9157-417

Highly sensitive refractive index sensor based on two cascaded microfiber knots with vernier effect Zhilin Xu, Qizhen Sun, Weihua Jia, Huazhong Univ. of Science and Technology (China); Perry Ping Shum, Huazhong Univ. of Science and Technology (China), Nanyang Technological Univ. (Singapore); Deming Liu, Huazhong Univ. of Science and Technology (China)

A highly sensitive refractive index (RI) sensor based on two cascaded microfiber knots with vernier effect is proposed and demonstrated by theoretical arithmetic. Deriving from high proportional evanescent field of microfiber and sharp spectrum fringes induced by vernier effect, a slight change ofbient RI will cause large variation of effective RI and significant wavelength shift of resonant peaks, indicating high sensitivity and resolution of the proposed compound resonator. Numerical analysis demonstrates a high sensitivity of 10000nm/RIU and a resolution of 5.57E-5 RIU at thebient RI around 1.33 for the fiber diameter of 1μm and cavity radii of R1=500μm, R2=547.62μm.

P26/Paper 9157-419

Highly sensitive temperature sensor based on D-shaped microfiber with high birefringence Haipeng Luo, Qizhen Sun, Zhilin Xu, Weihua Jia, Deming Liu, Huazhong Univ. of Science and Technology (China)

A high sensitive temperature sensor based on D-shaped microfiber with high birefringence is proposed and demonstrated. Experimental results demonstrate high temperature sensitivity up to -0.98921nm/oC within the range of 22oC-60oC.

P27/Paper 9157-430

Functionalization of exposed core fibers with multiligand binding molecules for fluorescence based ion sensing Roman Kostecki, Sabrina Heng, Heike Ebendorff-Heidepriem, Andrew D. Abell, Tanya M. Monro, The Univ. of Adelaide (Australia)

The results of functionalizing exposed-core optical fiber with multiligand binding sensor molecules for ion detection is presented. We show that the capacity of the sensor molecules to bind multiple ligands is negated when the sensor molecules are covalently bound, making the method ineffective where multiligand binding fluoroionophores are needed. An alternate functionalization method using thin film polymer doped with multiligand binding fluoroionophores is shown, demonstrating the ability for ion detection in a case where multiligand binding is needed. This one step functionalizing process for optical fiber sensing applications does not require surface attachment functional groups and has the potential to be inline with fiber drawing so that long lengths of functionalized fiber can be fabricated. P28/Paper 9157-434

Hollow-core fiber based linear cavity ring-down spectroscopy for gaseous oxygen detection Dorit Munzke, Michael Böhm, Oliver Reich, Univ. Potsdam (Germany)

We present a spectroscopic technique that combines the benefits of cavity ring-down spectroscopy and a hollow-core photonic crystal fiber. The 10m fiber is placed inside an optical cavity and acts both as the sample cell (volume = 442 nL) and waveguide. By measuring the ring-down time we demonstrate gaseous oxygen detection with an optical path length of up to 70m. As a figure of merit the volume per optical interaction path length is calculated to 6.3 nL m−1. This method is of interest for all applications where the sample volume of few nanoliters to microliters is the limiting factor. P29/Paper 9157-471

Sensing characteristics of long period gratings in hollow core fiber fabricated via electrode arc discharge Agostino Iadicicco, Univ. degli Studi di Napoli Parthenope (Italy); Antonello Cutolo, Univ degli Studi del Sannio (Italy); Stefania Campopiano, Univ. degli Studi di Napoli Parthenope (Italy)

This paper reports on the fabrication of Long Period Gratings (LPGs) in hollow-core air-silica photonic bandgap fibers (HC-PCFs) by using pressure assisted Electrode Arc Discharge (EAD) technique. In particular, the fabrication procedure relies on the combined use of EAD step, to locally heat the HC fiber, and of a static pressure (slightly higher than the external one) inside the fiber holes, to

modify the holes. Here, the experimental fabrication of LPG prototypes with different periods and lengths are discussed. And, the sensitivity of LPGs in HC-PCF to environmental parameters such as strain, temperature and static pressure are presented and discussed. P30/Paper 9157-504

Measurement of temperature profile in fiber Bragg gratings using whispering gallery modes M. Delgado-Pinar, I. L. Villegas, A. Díez, J. L. Cruz, M. V. Andrés, Univ. de València (Spain)

We present the measurement of the temperature variation along a fiber Bragg grating (FBG) written in a photosensitive fiber, using azimuthal whispering gallery modes (WGM) resonances of the fiber itself. The FBG is regarded as a cylindrical microresonator, in

he temperature of the grating increases at a given point. The temperature profile along the FBG is obtained by monitoring the WGM resonances at different points, as a function of the power and wavelength of the optical signal. Our experiments give useful information to study the small absorption changes produces by the standard UV photo-inscription technique and the thermally induced chirping effects generated when FBGs are used with moderate power levels. P31/Paper 9157-505

Novel Fiber Bragg grating sensor implemented in a polymer-core/silica-cladding hybrid optical fiber Zhijun Yan, Kaiming Zhou, Lin Zhang, Aston Univ. (United Kingdom)

A polymer-core/silica-cladding hybrid optical fiber is implemented by filling a capillary with UV-curable epoxy and a following UV-laser scanning exposure. A fiber Bragg grating is successfully inscribed in parallel using a phase mask. The experimental results show a reduced thermal response for the FBG and a theoretical analysis for such a hybrid optical fiber is performed which corroborates existing of a turning temperature for minimized thermal response. P32/Paper 9157-524

Relative humidity optical fiber sensors Haibin Ni, Ming Wang, Wei Chen, Nanjing Normal Univ. (China)

A kind of relative humidity sensors is presented. The sensors consist of a layer of three dimensional periodic films and an optical fiber bundle. The three dimensional periodic films which are polystyrene opal films, silica inverse opal films and composite photonic crystal films were self-assembled on end facet of the optical fiber bundle end facet. Principle of the sensor is that optical reflection peak of the three dimensional periodic films is sensitive to relative humidity, and optical reflection spectra of the films can be measured from the other end of the fiber bundle. P33/Paper 9157-342

Few millimeter-resolution Brillouin optical correlation domain analysis usingplified-spontaneous-emission pump and signal waves Raphael Cohen, Yosef London, Yair Antman, Avinoam Zadok, Bar-Ilan Univ. (Israel)

A new technique for Brillouin optical correlation domain analysis is proposed and demonstrated, in which the pump and signal waves are drawn from the filteredplified spontaneous emission of an erbium-doped fiberplifier. An estimated spatial resolution of 3.3 mm is obtained using a 33 GHz-wide source. The reconstruction of the Brillouin gain line and the recognition of a localized hot spot are demonstrated in a proof-of-concept experiment. Unlike phase-coded correlation domain analysis methods, the proposed scheme is not restricted by the bandwidth of available electro-optic modulators or pattern generators. Resolution is scalable to less than one millimeter. P34/Paper 9157-537

A photonic crystal fibre tip refractometer based on multimode interference Pengfei Wang, Dublin Institute of Technology (Ireland); Ming Ding, Univ. of Southampton (United Kingdom); Lin Bo, Yuliya Semenova, Dublin Institute of Technology (Ireland); Gilberto Brambilla, Univ. of Southampton (United Kingdom); Gerald Farrell, Dublin Institute of Technology (Ireland)

A compact singlemode-photonic crystal fibre-singlemode fibre tip (SPST) refractive index sensor is demonstrated in this paper. A CO2 laser cleaving is exploited to provide a clean-cut fibre tip which is then coated by a layer of gold to increase reflection. An average sensitivity of 39.1 nm/RIU and a resolvable index change of 2.56×10-4 are obtained experimentally with a ~3.2 µm diameter SPST. Because of its compactness, ease of fabrication, linear response, high sensitivity, easy connectivity to other fibreized optical components and low cost, this refractometer could find various applications in chemical and biological sensing. P35/Paper 9157-489

Combined time-domain and correlation-domain Brillouin analysis with 1600 meters range and 2 centimeters resolution David Elooz, Yair Antman, Avinoam Zadok, Bar-Ilan Univ. (Israel)

A combined time-domain and correlation-domain Brillouin sensing scheme is demonstrated. Pump and signal waves are phase modulated by a high-rate, perfect Golomb code, which confines their interaction to discrete, 2 cm-long correlation peaks. The properties of the code substantially reduce off-peaks interactions. The pump wave is alsoplitude modulated by a single pulse, so

thatplifications at different correlation peaks can be separated in the time domain. The Brillouin gain spectra at all 80,000 resolution points of a 1,600 m-long fiber are reconstructed experimentally, using only 127 scans per frequency. A 3 cm-long hot spot is recognized. P36/Paper 9157-539

In-line photonic crystal fiber optofluidic refractometer Chuang Wu, Jinan Univ. (China); Ming-Leung V. Tse, Zhengyong Liu, A. Ping Zhang, The Hong Kong Polytechnic Univ. (Hong Kong, China); Bai-Ou Guan, Jinan Univ. (China); Hwa-Yaw Tam, The Hong Kong Polytechnic Univ. (Hong Kong, China)

We report the fabrication and characterization of an in-line photonic crystal fiber optofluidic refractometer assisted by a C-shaped fiber. The C-shaped fiber spliced between the PCF and the SMF enables simultaneous in-line optical signal delivery and analyte fluid feeding. Using an arc discharge technique, we achieve selective exploitation of only the central two voids of the PCF for microfluidic sensing. Based on a Sagnac interferometer, a highly sensitive refractometer with sensitivity of 8699 nm/RIU and detection limit of 10E–6 for RI around 1.333 was achieved experimentally, which agrees well with the theoretical value of 8675 nm/RIU. P37/Paper 9157-541

Radiation hardening of FBG in harsh environments Adriana Morana, Sylvain Girard, Emmanuel Marin, Lab. Hubert Curien (France); Claude Marcandella, CEA, DAM, DIF (France); Jocelyn Périsse, Jean-Reynald Macé, AREVA (France); Aziz Boukenter, Lab. Hubert Curien (France); Marco Cannas, Univ. degli Studi di Palermo (Italy); Youcef Ouerdane, Lab. Hubert Curien (France)

The difficulties encountered in the implementation of a temperature or strain sensor based on Fiber Bragg Grating in a harsh radiative environment are introduced. We present the choices made to select both a radiation-resistant fiber in terms of transmission and also the grating inscription conditions necessary to write radiation tolerant FBGs in such fibers with a femto-second laser. The response of different classes of gratings was also studied under radiation at high doses (>1MGy). The comparison between F- and Ge-doped fibers was highlighted. P38/Paper 9157-552

Label-free biosensor based on a dual-core transversally chirped microstructured optical fiber Erick Reyes-Vera, Nelson Gomez-Cardona, Instituto Tecnologico Metropolitano (Colombia), Univ. Nacional de Colombia Sede Medellín (Colombia)

We present a novel sensing architecture consisting of a two-core transversally chirped microstructured optical fiber (MOF) suitable for label-free detection of molecules. The air holes of rings surrounding one core of the structure are functionalized for antibody detection by immobilization of an antigen sensor layer onto the walls of the holes. The change of the layer thickness of biomolecules can then be detected as a change in the device transmittance. Numerical calculations indicate that this novel structure can achieve acceptable level of sensitivity whereas the biosensor is mm long. P39/Paper 9157-580

Micro-electrodes system for electric field sensing with photonic liquid crystal fibers Tomasz R. Woliński, Marzena Tefelska, Sławomir Ertman, Karolina Mileńko, Rafał Łączkowski, Agata Siarkowska, Andrzej W. Domański, Warsaw Univ. of Technology (Poland)

In this paper we present the theoretical and experimental analysis of the micro-electrodes system for the for dynamic change of the electric field direction. The system consists of four micro-electrodes introduced into the micro-holes and one rectangular air hole in the center and can applied for electric field sensing with polymer-based micro-structured optical fibers infiltrated with liquid crystals. P40/Paper 9157-584

High temperature sensor based on an in-fibre Fabry-Perot cavity Oliver Schneller, Jinesh Mathew, William N. MacPherson, Robert R. J. Maier, Heriot-Watt Univ. (United Kingdom)

This paper presents the fabrication, characterization and encapsulation of a fibre optic temperature sensor based upon a micro Fabry-Perot (F-P) cavity. The F-P cavity is formed between a reflective in-fibre metallic splice and the air-fibre boundary at the end of the sensor. A change in temperature modifies the optical cavity length and this is observed as a shift in the reflected interference spectrum. The sensor can reliably operate for high temperature measurement up to 1000 °C. The temperature resolution of the sensor is < 10 °C. Furthermore a sealed off capillary is used to avoid strain transfer to the sensor in embedded applications. P41/Paper 9157-585

Analysis of the air holes' geometry influence on longitudinal strain sensitivity of microstructured fiber Bragg gratings Tadeusz Tenderenda, Karol Stepien, Military Univ. of Technology (Poland), InPhoTech Ltd. (Poland); Lukasz Szostkiewicz, InPhoTech Ltd. (Poland); Michal Murawski, Military Univ. of Technology (Poland), InPhoTech Ltd. (Poland); Michal Szymanski, Military Univ. of Technology (Poland); Martin Becker, Manfred Rothhardt, Hartmut Bartelt, Institut für Photonische Technologien e.V. (Germany); Pawel Mergo, Krzysztof Poturaj, Krzysztof Skorupski, Univ. of Maria Curie-Sklodowska (Poland); Pawel Marc, Leszek R. Jaroszewicz, Military Univ. of Technology (Poland); Tomasz Nasiłowski, Military Univ. of Technology (Poland), InPhoTech Ltd. (Poland), Univ. of Strathclyde ()

In this work we present a novel highly Ge doped microstructured fiber design dedicated for fiber Bragg grating (FBG) inscription and longitudinal strain sensing. Three series of the reported fiber differentiated by air hole diameters were drawn and presented. After numerical analysis of the propagation conditions (with effective refractive index, loss and mode area calculated) in the real structures, the fibers were subjected to femtosecond FBG inscription. We show the resulting typical FBG spectra, as well as measure the longitudinal strain sensitivity of the fabricated samples and its dependence on the microstructure geometry. P42/Paper 9157-587

Study of whispering gallery modes in a cylindrical microresonator excited by a tilted fiber taper Vishnu Kavungal, Lin Bo, Qiang Wu, Dublin Institute of Technology (Ireland); Mianzhen Teng, Chongxiu Yu, Beijing Univ. of Posts and Telecommunications (China); Gerald Farrell, Yuliya Semenova, Dublin Institute of Technology (Ireland)

We studied the excitation of whispering gallery modes (WGMs) in a cylindrical microresonator formed by a short length of a multimode fiber. The light was evanescently coupled into the fiber from a micro-cylinder whose tilt angle was varied from perpendicular to parallel with respect to the fiber taper. Narrow WGM resonances are observed in the transmission spectrum of the fiber taper with a maximum Q factor of ~10^5. Evolution of the transmission spectrum with the change of tilt angle involved changes in the number of WGMs in the spectrum for smaller tilts and the disappearance of WGM resonances at large tilt angles. P43/Paper 9157-604

Delamination-diagnosis-method for adhesively surface-applied FBG strain sensors Eugen Baitinger, Vivien Schukar, Nadine Kusche, Constanze Schilder, Bundesanstalt für Materialforschung und -prüfung (Germany)

Delamination growth and debonding of surface-applied fiber Bragg grating (FBG) strain sensors lead to spectral deformation of the reflected spectrum. The FBG spectrum shape is sensitive to the partial debonding of the sensor and therefore this information can be used to describe delamination growth. The developed analytical method to determine degree and direction of debonding and the additional experimental investigations show a possible way of qualifying and evaluating the interface performance of adhesively applied sensors. P44/Paper 9157-615

Improvement in refractive index sensitivity by means of internally curved long period fiber gratings Francesco Chiavaioli, Cosimo Trono, Francesco Baldini, Istituto di Fisica Applicata Nello Carrara (Italy)

A novel configuration of long period fiber grating (LPFG), based on a specially designed refractive index (RI) profile, was manufactured and studied. The internally manufactured geometric structure is characterized by grating planes tilted at increasing angles, as moving away from the center of symmetry of the structure towards its both edges. This structure reproduces the bending of an optical fiber and improves the RI sensitivity of an LPG to the external surrounding medium. A three-fold enhancement in the RI sensitivity was experimentally proved, thus giving a further contribution towards the development of more sensitive RI sensors based on optical fiber LPGs. P45/Paper 9157-624

Optical fiber hydrogen sensor based on polarization-maintaining photonic crystal fiber Yuanhong Yang, Fuling Yang, Huan Wang, Xungang Diao, Qirong Liu, BeiHang Univ. (China)

An intrinsic optical fiber hydrogen sensor based on polarization-maintaining photonic crystal fiber (PM-PCF) Sagnac interferometer was proposed. The facing target sputtering technique with special Pd/Ag plate target structure was developed to deposit Pd/Ag composite film on PM-PCF. The characteristic of Pd/Ag film was measured and analyzed. An experimental setup for hydrogen sensing was built. the wavelength at different hydrogen concentration and the temperature interference were tested. The results shown the sensitivity was higher at low concentration range and good repeatability was obtained within measuring range of 4%. And the temperature affect was weak with special PM-PCF. P46/Paper 9157-631

Multiwavelength fiber lasers based on spatial mode beating for high resolution linear and angular displacement sensing Nan-Kuang Chen, Yung-Hsiang Chang, National United Univ. (Taiwan); Wood-Hi Cheng, National Sun Yat-sen Univ. (Taiwan); Tuan Guo, Bai-Ou Guan, Jinan Univ. (China)

We demonstrate multiwavelength fiber lasers by incorporating the micro Michelson interferometer with spatial mode beating phenomenon, which comes from the interferencesong cladding modes, into ring cavity for high resolution linear and angular displacement sensing. P47/Paper 9157-568

Optical fiber current transducer using lossy mode resonances for high voltage networks Joaquin Ascorbe, Jesus M. Corres, Ignacio R. Matias, Francisco J. Arregui, Univ. Pública de Navarra (Spain)

This work presents the development and characterization of an optical fiber current transducer based on lossy mode resonances (LMRs) to work in high voltage networks. A multilayer structure was created in order to be able to shift the LMR by an electro-optic

material deposited in the middle of two electrodes. The optical resonance has a displacement range of 200 nm on its TM component, what makes this device suitable for current sensing. Furthermore, dip coating of polyvinylidene difluoride has enhanced the nanofilm uniformity with respect to previous devices. P48/Paper 9157-595

Microfiber coupler based biosensor incorporating a layer of gold nanoparticles with improved sensitivity Yuliya Semenova, Lin Bo, Pengfei Wang, Furong Tian, Hugh Byrne, Gerald Farrell, Dublin Institute of Technology (Ireland)

We studied the effect of a star-shaped gold nanoparticles layer coated on the surface of the microfiber coupler (MFC) on the sensitivity of the embedded MFC biosensor. It is shown that deposition of the layer of star-shaped gold nanoparticles on the MFC sensor surface results in a significantly increased spectral shift (on average 3.05 nm shift compared to a 1.08 nm shift per layer of electrolyte for the sample without the nanoparticles layer). In addition, introducing the nanoparticles layer results in the decrease of the transmission power; measurement of the changes in transmission also could be used as a means for the sensor interrogation. P49/Paper 9157-671

Optical fiber Bragg grating mesh for multiphase flow sensing Carlos R. Zamarreño, Univ. Pública de Navarra (Spain); Cicero Martelli, PUC/RJ (Brazil); Virgínia Baroncini, Eduardo N. dos Santos, Marco J. da Silva, Rigoberto E. M. Morales, Univ. Tecnológica Federal do Paraná (Brazil); I. R. M. Maestro, Francisco J. Arregui, Univ. Pública de Navarra (Spain)

This work introduces a new approach to characterize the multiphase flow by means of the utilization of optical fiber Bragg gratings. Here, the force applied by the air/liquid flow on the fiber gratings is the underlying mechanism of these sensors. Flow images are constructed from the response of a 8x8 mesh of sensors, with a total of 16 different FBGs multiplexed in wavelength. The data from each sensor has been processed in order to obtain a 2D plot of the air/liquid phase as well as a 3D plot of the air bubbles inside the tube for each time interval. P50/Paper 9157-8

Application of fiber Bragg grating sensors in light aircraft: ground and flight test Jin-Hyuk Kim, Pratik Shrestha, Yurim Park, Chun-Gon Kim, KAIST (Korea, Republic of)

Fiber optic sensors are being spotlighted as the means to monitoring aircraft conditions due to their excellent characteristics. This paper presents an affordable structural health monitoring system based on a fiber Bragg grating sensor (FBG) for application in light aircrafts. A total of 24 FBG sensors were installed in the main wing of the test bed aircraft. In the ground test, the intactness of the installed sensors and device operability were confirmed. During the flight test, the strain and temperature responses of the wing structure were measured by the on-board low-speed FBG interrogator. The measured strains were successfully converted into the flight load history through the load calibration coefficient obtained from the ground calibration test. P51/Paper 9157-14

An oil and gas pipeline pre-warning system based on Φ-OTDR Dongjie Tan, Xiaozhong Tian, Wei Sun, Yan Zhou, Lu Liu, Yunbin Ma, Jia Meng, Hong Zhang, China National Petroleum Corp. (China)

Based on phase-sensitive optical time domain reflectometer (Φ-OTDR), an oil and gas pipeline pre-warning system is demonstrated and applied to monitor products pipeline laying along an optical cable. Theoretically, the longest monitor distance can be as long as the coherent length of light source through connecting repeater opticalplifiers, which canplify not only pulse light but also Rayleigh scattering light. An appropriate algorithm derived from support vector machine (SVM) is developed to identify and classify different vibration signals along pipeline, including artificial digging, mechanical excavation and vehicles crossing. Field test in Gangzao pipeline shows that the pre-warning system can detect artificial digging within 5m, mechanical excavation and vehicles crossing within 50m. P52/Paper 9157-31

Fiber optical magnetic field sensor for power generator monitoring Michael Willsch, Thomas Bosselmann, Michael Villnow, Siemens AG (Germany)

Inside of large electrical engines such as power generators and large drives there are extreme electric and magnetic fields which cannot be measured electrically. Novel fiber optical magnetic field sensors are being used to characterize the magnetic fields for design validation. In the future condition monitoring could help for early detecting of inner faults. P53/Paper 9157-39

Raman distributed temperature sensor for oil leakage detection in soil: a field trial and future trends Alessandro Signorini, Tiziano Nannipieri, Scuola Superiore Sant'Anna (Italy); Luca Gabella, Photonic Networks National Lab. (Italy); Fabrizio Di Pasquale, Scuola Superiore Sant'Anna (Italy); Gilberto Latini, Daniele Ripari, Saipem S.p.A. (Italy)

Field validation of distributed Raman temperature sensing (RDTS) for oil leakage detection in soil was performed. The RDTS capability in detecting and locating, with high accuracy and spatial resolution, is demonstrated through a water leakage simulation in a field trial. Future trends and potentials of this technology in oil&gas field for long pipelines are then outlined by reporting lab experiments demonstrating accurate meter-scale temperature measurement over more than 50 km of standard single mode fiber. The proposed

solution, based on distributed Simplex coding techniques, can be competitive in terms of cost and performance with respect to other distributed sensing technologies. P54/Paper 9157-54

Fiber optic sensor for methanol quantification in biodiesel Marianne S. Kawano, Ricardo Canute Kamikawachi, José L. Fabris, Marcia Müller, Univ. Tecnológica Federal do Paraná (Brazil)

In this work a refractometric sensor for assessment of methanol presence in biodiesel is reported. The transducer relies on the interference between the forward and back propagating modes of a single long period grating, written close to an end-face mirror optical fiber. The sensing method is thermally assisted in order to overcome the drawback caused by the high refractive index (close to the fiber cladding index) of methanol-biodiesel blends at low temperatures. Sensor showed a combined standard uncertainty of 0.6 % v/v of methanol in biodiesel for a confidence level of 68.27%, within the methanol concentration ranging from 0 to 25 % v/v. P55/Paper 9157-100

Field test of a fully distributed fiber-optic intrusion detection system for long-distance security monitoring of national borderline Huijuan Wu, Zinan Wang, Fei Peng, Zhengpu Peng, Xiaoyu Li, Yu Wu, Yunjiang Rao, Univ. of Electronic Science and Technology of China (China)

In this paper, we presented a successful field test of a fully distributed fiber-optical intrusion detection system for security monitoring of 220km long national borderline in China. Such a fiber fence shows its outstanding ability to operate at extreme weather conditions, like strong wind, heavy snow and storm, wide temperature range from -55℃ to +50℃, et al, which may be the most difficult and complicated environment for practical applications of fiber fences. P56/Paper 9157-106

Optical fiber Fabry-Perot pressure sensor based on SU-8 Jiali Zhu, Lihua Dai, Ming Wang, Dongyan Cai, Hua Rong, Sheng Jia, Jingjing You, Nanjing Normal Univ. (China)

A novel optical MEMS pressure sensor with a SU-8, microstructure is proposed. SU-8 photoresist is used to form the high aspect ratio structure on silicon wafer. The advantage of the novel structure mainly lies in the design of separating sensing membrane deformation with the length change of Fabry–Perot cavity. The principle of the pressure measurement has been introduced. The mechanical model is analyzed and parameters of SU-8 structure are determined by simulation. The fabrication process is described. Experimental results demonstrate that the sensor has a reasonable linearity, sensitivity under micro-pressure measurement range from 0 to 0.1 MPa. P57/Paper 9157-129

In-service communication channel sensing based on reflectometry for TWDM-PON systems Daisuke Iida, Shigeru Kuwano, Jun Terada, NTT Access Network Service Systems Labs. (Japan)

Many base stations are accommodated in TWDM-PON based mobile backhaul and fronthaul networks for future radio access, and failed connections in an optical network unit (ONU) wavelength channel severely degrade system performance. A cost effective in-service ONU wavelength channel monitor is essential to ensure proper system operation without failed connections. To address this issue we propose a reflectometry-based remote sensing method that provides wavelength channel information with the optical line terminal (OLT)-ONU distance. The method realizes real-time monitoring of ONU wavelength channels without signal quality degradation. Experimental results show it achieves wavelength channel distinction with high distance resolution. P58/Paper 9157-154

Refractive index and viscosity: dual sensing with plastic fibre gratings Ricardo Ferreira, Lúcia Bilro, Carlos Marques, Ricardo Oliveira, Rogério Nogueira, Instituto de Telecomunicações (Portugal)

A refractive index and viscosity sensor based on FBGs in mPOF is reported for the first time. The refractive index was measured with a sensitivity of -10.98nm/RIU and a resolution of 1x10-4 RIU. Viscosity measurements were performed with acousto-optic modulation, obtaining a sensitivity of -94.42%/mPa.s and a resolution of 0.06mPa.s. P59/Paper 9157-176

Production and characterization of Bragg gratings in polymer optical fibers for sensors and optical communications Ricardo Oliveira, Carlos Marques, Lúcia Bilro, Rogério Nogueira, Instituto de Telecomunicações (Portugal)

The inscription of Bragg gratings in different POFs, including GI-POF is presented. Additionally the cross-sensitivity characterization to temperature and strain for an mPOF FBG is reported for the first time. Results show better sensitivity performances after the annealing process which will help to develop new sensitive optical devices. P60/Paper 9157-194

Noncontact photoacoustic tomography using optical fiber-based heterodyne interferometer

JongHyun Eom, Seong Jun Park, Young Ho Kim, Gwangju Institute of Science and Technology (Korea, Republic of); Chang Su Lee, The Univ. of Suwon (Korea, Republic of); Byeong Ha Lee, Gwangju Institute of Science and Technology (Korea, Republic of)

We propose the noncontact photoacoustic tomography system that reads the acoustic signal by using an optical fiber-based heterodyne interferometer. The surface displacement of a specimen, resulting from the acoustic wave generated by irradiation of a laser pulse and its absorption inside the specimen, is optically measured by the heterodyne interferometer. With the data set of the surface displacement, the photoacoustic image of the specimen is reconstructed by a Fourier transform based reconstruction algorithm. This proposed method is experimentally evaluated by using a phantom sample that contains PET fibers.

P61/Paper 9157-297

Investigation of low-cost two-wavelength interrogation for integration of different fiber optical temperature sensors into electric power facility monitoring systems Michael Willsch, Joachim Kaiser, Thomas Bosselmann, Siemens AG (Germany); Torsten Wieduwilt, Reinhardt Willsch, Institut für Photonische Technologien e.V. (Germany)

Several fiber optical temperatur sensor systems are commercially available. However for many industrial and electrical power applications very simple and cost effective solutions are required which easely can be integrated into existing condition monitoring facilities. A simple two wavelength interrogation system has been designed and combined with the most appropriate fiber optical temperatur probes to serve applications in electrical power generation. . P62/Paper 9157-319

FBG system for temperature monitoring under electromagnetic immersed and harsh oil and gas reservoir environment Michael Villnow, Thomas Bosselmann, Michael Willsch, Joachim Kaiser, Siemens AG (Germany)

A common way to explore oil out of tar sand is to use a technique called Steam Assisted Gravity Drainage SAGD. This method can be enhanced by using an inductive heater (EM-SAGD). To monitor the heat dissipation of the inductor a measurement system for this harsh electromagnetic environment is needed. In this paper different optical temperature measurement systems are compared to find the most suitable system for this kind of application. A field test with great results was performed, where the performance of the inductor and the FBG measurement system were demonstrated. P63/Paper 9157-325

A novel wireless mobile platform integrated with optical fibre sensors Bochao Zhou, Shuo Yang, Tong Sun, Kenneth T. V. Grattan, City Univ. London (United Kingdom)

This paper presents a novel design of wireless mobile platform which enables effective integration of a number of optical fibre sensors with an advanced mobile wireless sensor network (WSN) and allows for potential applications such as monitoring in remote and harsh environments and tracking, exploiting fully the advantages offered both by mobile WSN and by advanced optical fibre sensing technologies. The platform which was designed and implemented consists of an optical fibre sensor module and a smart mobile WSN module, which shows important advantages for mobile sensing and tracking and mesh networking. P64/Paper 9157-348

Characterisation of radioluminesence based optical fibre dosimeter in radiotherapy beam applications Peter Woulfe, Galway Clinic (Ireland); Sinead O'Keefe, Elfed Lewis, Denis McCarthy, Univ. of Limerick (Ireland); Mark Grattan, Belfast City Hospital (United Kingdom); John Cronin, Galway Clinic (Ireland)

A PMMA (polymethyl methacrylate) based plastic optical fibre is coated with radiation sensitive inorganic scintillators that fluoresce when exposed to ionising radiation. The emitted signal penetrates the fibre and propagates along the fibre where it is remotely monitored using a fluorescence spectrometer. The dosimeter is characterised for a range of parameters associated with radiotherapy treatment plans, including field size and dose rate. The results demonstrate good repeatability, with a maximum percentage error of 0.59% and the response is independent of dose rate. P65/Paper 9157-371

Field test of microbend fiber sensor for hospital use Zhihao Chen, A*STAR Institute for Infocomm Research (Singapore); Doreen Lau, Singapore General Hospital (Singapore); Ju Teng Teo, Soon Huat Ng, Xiufeng Yang, A*STAR Institute for Infocomm Research (Singapore); Pin Lin Kei, Singapore General Hospital (Singapore)

In this paper, we report a field test of a microbend fiber sensor for simultaneous measurement of breathing rate, breathing pattern, Ballistocardiogram and heart rate during magnetic resonance imaging (MRI). Comparative experiments conducted between our sensor and commercial physiologic device on a healthy male subject showed an accuracy of +/-2bpm for simultaneous measurement of both breathing rate and heart rate. Our preliminary field test on simultaneous measurement of breathing rate and heart rate in a clinical trial conducted on 11 healthy subjects in the 3.0 Tesla MRI environment showed very good agreement compared with measurements obtained from conventional MR-compatible devices. P66/Paper 9157-380

Performance of a 400km interrogated fiber-optics hydrophone array Chunyan Cao, Shuidong Xiong, Qiong Yao, Zhengliang Hu, Yongming Hu, National Univ. of Defense Technology (China)

We designed and constructed a 400km interrogated fiber-optics hydrophone (FOH) array for the bottom mounted applications. The experimental results show that the phase noise level of the remote array is -97dB re 1rad/sqrt(Hz) @1kHz, the maximum time division multiplexing (TDM) crosstalk level is -54dB, the wavelength division multiplexing (WDM) crosstalk level is better than -73dB and the signal correlation between two sensors is better than 0.98. The results demonstrate that the performance of this remote array has reached to an acceptable high level, so this architecture would be of great importance in the practical applications.

P67/Paper 9157-386

Evaluation of Brillouin frequency shift and its temperature dependence in poly(pentafluorostyrene)-based polymer optical fibers by ultrasonic pulse-echo technique Kazunari Minakawa, Tokyo Institute of Technology (Japan); Kotaro Koike, Keio Univ. (Japan), New York Univ. (United States); Neisei Hayashi, Tokyo Institute of Technology (Japan); Yasuhiro Koike, Keio Univ. (Japan); Yosuke Mizuno, Kentaro Nakamura, Tokyo Institute of Technology (Japan)

We investigated the potential of a poly(pentafluorostyrene)-based polymer optical fiber (PPFS-POF), which is a promising alternative for a costly perfluorinated graded-index (PFGI-) POF, as a Brillouin-based temperature sensing fiber. The temperature dependence of the Brillouin frequency shift of PPFS was estimated using an ultrasonic pulse-echo technique. In temperature range from 20 to 75 °C, the dependence was linear with no hysteresis, and the temperature coefficient, which determines the sensitivity, was approximately –7.1 MHz/K at 850 nm independently of the molecular weight and was nearly identical to that in a PFGI-POF. P68/Paper 9157-389

Discriminative measurement of strain and temperature using Brillouin scattering and fluorescence in erbium-doped optical fiber Mingjie Ding, Yosuke Mizuno, Kentaro Nakamura, Tokyo Institute of Technology (Japan)

A novel discriminative strain and temperature measurement is demonstrated using Brillouin scattering and fluorescence in an erbium-doped fiber (EDF). The fluorescence intensity ratio, calculated using the fluorescence intensities (or powers) at 1530 nm and at 1565 nm, is linearly dependent on temperature with a proportionality constant of 7.5 × 10E–4 /°C, but is not influenced by strain. By combining the strain- and temperature-dependences of Brillouin frequency shift in EDFs, the applied strain of 0.4% and the temperature of 20.0°C were successfully discriminated with measurement errors of 0.03% and 0.6°C, respectively. P69/Paper 9157-402

Long-gauge FBGs interrogated by DTR3 for dynamic distributed strain measurement of helicopter blade model Michiko Nishiyama, Hirotaka Igawa, Tokio Kasai, Japan Aerospace Exploration Agency (Japan); Naoyuki Watanabe, Tokyo Metropolitan Univ. (Japan)

In this paper, we describe characteristics of distributed strain sensing based on a Delayed Transmission/Reflection Ratiometric Reflectometry (DTR3) scheme with a long-gauge Fiber Bragg Grating (FBG), which is attractive to dynamic structural deformation monitoring such as a helicopter blade and an airplane wing. The DTR3 interrogator using the long-gauge FBG has capability of detecting distributed strain with 50 cm spatial resolution in 100 Hz sampling rate. We evaluated strain sensing characteristics of the long-gauge FBG attached on a 5.5 m helicopter blade model in static tests and free vibration dynamic tests. P70/Paper 9157-423

Miniaturized total temperature probe based on fibre Bragg gratings Leonhard Polz, Tasja Berghaus, Markus Klose, Munich Univ. of Applied Sciences (Germany); Andreas Zeisberger, MTU Aero Engines (Germany); Hartmut Bartelt, Institut für Photonische Technologien e.V. (Germany); Johannes Roths, Munich Univ. of Applied Sciences (Germany)

A miniaturized design of a fibre-optic based total temperature probe is presented which is intended to be used for aircraft engine testing. The FBG-based probes were experimentally characterized in the harsh environment of an open jet test bench at air stream velocities up to Mach numbers of 0.8 and they showed similar performance as conventional sensing techniques. The reduction of the size of the transducer was possible by using small sized FBG-based temperature sensors. Due to the smaller probe design and thinner signal transmission cables, less distortion of the air stream is expected with the fibre-optic sensor, when compared to conventional instrumentation. This allows a higher density of instrumented sensors and thus a higher spatial resolution of the measurement. This is, to our knowledge, the first demonstration of total temperature measurements at high air stream velocities with FBG-based transducers. P71/Paper 9157-448

Magnetic field sensor utilizing bent fiber taper and magnetic fluid Jie Li, Zhuang Tian, Li-Peng Sun, Bai-Ou Guan, Jinan Univ. (China)

A magnetic field sensor is demonstrated by placing a bent-fiber taper modal interferometer inside a magnetic fluid sealed with an organic glass base. Owing to the strong refractive index dependency of the interferometer and magneto-optics property of the fluid, our sensor exhibits high sensitivity to the external magnetic field change. A linear wavelength dependency of ~58pm/Oe is

experimentally obtained within a magnetic field range from 30 to 80 Oe. Our structure is featured of high sensitivity, fiber-compatibility, compactness, and robustness. P72/Paper 9157-467

Radiation hard fiber optic thermo-hygrometers for relative humidity detection in the CMS experiment at CERN Gaia Maria Berruti, Marco Consales, Univ. degli Studi del Sannio (Italy); Michele Giordano, IMCB-CNR (Italy); Salvatore Buontempo, INFN (Italy); Giovanni Breglio, Univ. degli Studi di Napoli Federico II (Italy); Makovec Alajos, Univ. of Debrecen (Hungary); Paolo Petagna, CERN (Switzerland); Andrea Cusano, Univ. degli Studi del Sannio (Italy)

This work investigates the performances and the radiation hardness capability of optical thermo-hygrometers based on Fiber Bragg Gratings (FBG) technology for humidity monitoring in the Compact Muon Solenoid experiment (CMS) at CERN, in Geneva. Extensive characterizations in terms of sensitivity, repeatability and accuracy on 80 specially produced polyimide-coated FBG sensors and 80 commercial temperature FBG sensors are presented. Progressive irradiation campaigns with γ- ionizing radiations were also performed. Results showed that the sensors sensitivity is unchanged after each radiation exposure; while the wavelength peak exhibits a radiation-induced shift. The saturation properties of this shift are discussed. P73/Paper 9157-468

Fiber bragg grating sensor as valuable technological platform for new generation of superconducting magnets Antonella Chiuchiolo, Marta Bajko, Juan Carlos Perez, Hugues Bajas, Patrick Viret, CERN (Switzerland); Marco Consales, Univ. degli Studi del Sannio (Italy); Michele Giordano, Institute for Composite and Biomedical Materials, CNR (Italy); Giovanni Breglio, Univ. degli Studi di Napoli Federico II (Italy); Andrea Cusano, Univ. degli Studi del Sannio (Italy)

New generation of superconducting magnets for high energy applications designed, manufactured and tested at the European Organization for Nuclear Research (CERN) require the implementation of reliable sensors able to monitor the mechanical stresses affecting the winding from fabrication to operation in magnetic field of 13 T. This work deals with the embedding of Fiber Bragg Grating sensors in a short model Nb3Sn dipole magnet in order to monitor the strain developed in the coil during the cool down to 1.9 K, the powering up to 15.8 kA and the warm up, offering perspectives for the replacement of standard strain gauges. P74/Paper 9157-482

A mechanical filter for FBG accelerometers Marco Bocciolone, Giuseppe Bucca, Andrea Collina, Lorenzo Comolli, Politecnico di Milano (Italy)

Many applications are characterized by very severe environment from the sensors point of view. An example is the railway field, where often the measurement setup is subjected to high voltage and electromagnetic emission. In these work conditions, optical sensors are more suitable than electrical ones due to their characteristics. In this paper, the acceleration measurements are taken into account. Nowadays many optical accelerometers are present on the market. In particular, in this work FBG accelerometers are considered. This kind of sensors is characterized by an undamped resonance that can produce the break of the sensor. One possibility to avoid this problem is to add a damping effect in order to reduce the resonanceplification. In the following section, the method to reproduce a mechanical filter able to increase the damping coefficient of the sensor is presented. Experimental results in laboratory will be discussed, showing the effectiveness of the solution. P75/Paper 9157-498

Wavelength domain multiplexed fiber specklegram sensor Luis Rodriguez, Mauro Lomer, Adolfo Cobo, Univ. de Cantabria (Spain)

In this work, a low-cost WDM interrogation system has been proposed and experimentally tested to obtain two independent channels of a fiber specklegram sensor. Two lasers of different wavelengths have been launched into two multimode Polymer Optical Fibers (POFs) and then combined through a coupler before their interrogation using a RBG camera. By analyzing each color of the video sequence, the two fiber channels can be independently obtained. Besides, the speckle sensitivity has been also studied by analyzing different properties of speckle patterns such as their contrast or the speckle size. The achieved results help to the development of new fiber specklegram sensors by allowing a direct comparison between two specklegrams of different properties P76/Paper 9157-526

FBG sensors for deformation monitoring of a tracking particle detector: preliminary results Agostino Iadicicco, Univ. degli Studi di Napoli Parthenope (Italy); Massimo Della Pietra, Univ. degli Studi di Napoli Parthenope (Italy), Istituto Nazionale di Fisica Nucleare, Sezione di Napoli (Italy); Stefania Campopiano, Univ. degli Studi di Napoli Parthenope (Italy)

This paper reports on feasibility analysis of the use of FBGs for the deformation monitoring of a micromegas (MM) tracking particle detector to be realized at CERN. One mandatory issue for the MM detector is a precise monitoring of its deformation. To this aim, in this work FBG strain sensors are proposed and experimentally investigated to monitor bending and deformation on a miniaturized MM support panel. The obtained results confirm that FBG sensors, that tolerate high radiation, are able to monitor deformation and curvature in accord with high energy physics requirements.

P77/Paper 9157-553

Research activities to push standardization of fibre-optic strain sensors Wolfgang R. Habel, Bundesanstalt für Materialforschung und -prüfung (Germany)

Performance description of fiber-optic sensor products is mostly well done; however, the performance of sensors when applied in rather harsh environment is different from those determined in laboratory before installation. Performance of applied sensors is difficult to define. Standardized procedures for evaluation of the sensor performance after application or integration into materials are necessary. The difficulty to evaluate on-site the mechanical behavior or physical and chemical processes in the sensing zone of strain sensors is described for sensors installed in offshore environment. The paper refers on current standardization activities and corresponding research activities to develop guidelines for application and integration. P78/Paper 9157-608

Fibre optic monitoring system for the determination of segment joint movements inside a hydro power dam Helmut Woschitz, Ferdinand Ferdinand Klug, Werner Lienhart, Graz Univ. of Technology (Austria)

In recent years hydro power stations were rebuilt to more efficient pumped storage power stations. This changed the loading conditions and new monitoring concepts are required. We developed a FBG based automatic monitoring system for the simultaneous measurement of concrete segment joints. With a fibre optic testing facility sensor nonlinearity and hysteresis effects were investigated. Using selected sensors the requested accuracy of 0.02 mm for deformations up to 3 mm can be achieved. Several sensors were installed in a hydro power dam. First results show an increased number of load cycles and smaller movements for the dam in pumping mode. P79/Paper 9157-643

Performance analysis simulation of new SPR microstructured D-type optical fiber sensor configurations for refractive index measurement Diego F. Santos, Univ. da Madeira (Portugal); Ariel Guerreiro, Univ. do Porto (Portugal), INESC TEC (Portugal); José M. Baptista, Univ. da Madeira (Portugal), INESC TEC (Portugal)

This paper presents the performance analysis of two new sensing configurations of refractive index based on surface plasmon resonance (SPR) in microstructured D-type optical fiber with a thin gold layer using simulations obtained with COMSOL Multiphysics. The configurations are analyzed in terms of the intensity of the electric field. The results are compared with a conventional SPR D-type optical fiber sensor for refractive index measurement. P80/Paper 9157-661

Field test of the flow noise of fiber laser hydrophone array Wentao Zhang, Wenzhu Huang, Yingbo Luo, Zhaogang Wang, Fang Li, Institute of Semiconductors (China)

Fiber laser hydrophone has attracted more and more attention because of its potential application in novel sonar system. For a towed fiber optic hydrophone array, the flow noise is an important source of the system noise. This paper presents the field test result of the flow noise of an eight-element fiber laser hydrophone array. The structure of the fiber laser hydrophone and the array is also introduced. The field test shows that obvious flow noise can be measured when the array is towed at the speed of 3 kn. P81/Paper 9157-664

Condition monitoring of a subsea pump using fibre optic sensing Chris Staveley, Smart Fibres Ltd. (United Kingdom)

With the growth in deep-water oil and gas production, condition monitoring of high-value subsea assets to give early warning of developing problems is vital. Offshore operators can then transport and deploy spare parts before a failure occurs thus minimizing equipment down- time. Results are presented from a suite of tests in which multiple elements of a subsea twin-screw pump were monitored using a single fibre optic sensing system that simultaneously measured dynamic strain on the main rotor bearings, pressure and temperature of the lube oil, distributed temperature through the motor stator windings and vibration of the motor housing.

P82/Paper 9157-34

Structural health monitoring with fibre optic sensors Alfredo GÚEMES, Antonio Fernandez-Lopez, Univ. Politecnica Madrid (Spain)

SHM is defined as the process of acquiring and analyzing data from on-board sensors to evaluate the health of a structure. Most common damages on aircrafts are local cracks and delaminations, that do not change strongly the overall strain field, but that will act as the failure initiation point. Fiber optic sensors act primarily as strain sensors, so unless damage happens very close to the sensor location, it may go undetected. Currently, three main approaches for detecting damage from strain measurements are being investigated: 1) High resolution fibre optic distributed sensing (OFDR Rayleigh scattering). 2) Strain mapping with a dense network of sensors. Statistical analysis tools, like PCA, have been successfully used. 3) Hybrid FBG/PZT systems. FBGs must detect the ultrasonic elastic waves. P83/Paper 9157-91

Monitoring the energy efficiency of buildings with Raman DTS and embedded optical fiber cables Pierre G. Ferdinand, CEA/Saclay (France); M. Giuseffi, Lab. de Mesures Optqiues, CEA (France); N. Roussel, S. Rougeault, Lab. de Mesures Optiques, CEA (France); O. Fléchon, V. Barentin, Lab. Energétique du Bâtiment, Parc Savoie Technolac (France)

To reduce greenhouse gas emissions and to promote energy savings in the building sector, a project named Batimetre has been set-up, to measure parameters affecting building energy consumption. For the first time, optical fibers have been deployed on internal and external faces of two experimental houses, designed for low energy consumption. With a DTS Raman system, these cables provide a distributed measurement of walls temperature every meter and every two minutes. Such instrumentation is able to deliver a very large number of data at a reduced operating cost. It allows to isolate thermal phenomena in dynamic thermal simulation tools, and to compare several intermediate predicted and measured parameters. P84/Paper 9157-111

High-resolution high-sensitivity and truly distributed optical frequency domain reflectometry for structural crack detection Wenhai Li, Xiaoyi Bao, Liang Chen, Univ. of Ottawa (Canada)

Optical Frequency Domain Reflectometry (OFDR) with the use of polarization maintaining fiber (PMF) is capable of distinguishing strain and temperature, which is critical for successful field applications such as structural health monitoring (SHM) and smart material. Location-dependent measurement sensitivities along PMF are compensated by cross- and auto-correlations measurements of the spectra form a distributed parameter matrix. Simultaneous

P85/Paper 9157-218

A real-time inclinometer based on an etched fiber Bragg grating connected to hollow-core fiber Qiang Zhang, Tao Zhu, Fengyang Yin, Chongqing Univ. (China); Kin Seng Chiang, City Univ. of Hong Kong (Hong Kong, China); Ming Deng, Chongqing Univ. (China)

We propose and experimentally demonstrate a low-cost, compact temperature-insensitive inclinometer, which is constructed by connecting a chemically etched fiber Bragg grating to a hollow-core fiber filled with tin. The optical power reflected from the grating is linearly proportional to the inclination angle of the grating and can provide a real-time measure of the inclination angle. Our

e interference. P86/Paper 9157-292

Reinforced concrete structural corrosion monitoring using Hi-Bi photonic crystal fibres in a fiber loop structure Mikel Bravo Acha, Univ. Pública de Navarra (Spain); Colum McCague, Matthias Fabian, City Univ. London (United Kingdom); Leszek R. Jaroszewicz, Military Univ. of Technology (Poland); Pawel Mergo, Univ. of Maria Curie-Sklodowska (Poland); Manuel Lopez-Amo, Univ. Pública de Navarra (Spain); Kenneth T. V. Grattan, Tong Sun, City Univ. London (United Kingdom)

A novel sensing approach has been developed for in-situ corrosion monitoring of steel in reinforced concrete structures, using a fibre loop interferometer sensor system based on a Hi-Bi photonic crystal fibre (PCF). To do so an accurate fibre alignment procedure has been implemented in order to improve the performance of the sensor system embedded into the concrete structure when it is subjected to an accelerated corrosion test. The positive results obtained have confirmed the effectiveness of such a sensor system for applications in structural health monitoring. P87/Paper 9157-303

Effects of elongation on polymer optical fiber power losses for sensing purposes David S. Montero, Juan Carlos Torres, Jorge Zahr Viñuelas, José Luis Pérez Castellanos, Carmen Vázquez García, Univ. Carlos III de Madrid (Spain)

In this work, we explore the variation of power losses of PMMA-core plastic optical fiber through tensile tests. Experimental results of received optical power during elastic and plastic deformation process demonstrate the feasibility of POFs as simple intensity-based fiber-optic sensors for Structural Health Monitoring applications beyond complex schemes. A theoretical approach of the POF behavior versus strain is also provided. P88/Paper 9157-383

Carbon fibre-foam sandwich composite laminate embedded with fiber Bragg grating sensors Ginu Rajan, Evan Darminan, Gang-Ding Peng, Gangadhara Prusty, Univ. of New South Wales (Australia)

Carbon fibre-foam sandwich composite with embedded FBGs are fabricated and dynamic load testing and temperature studies were carried out. It was found from the tests that, the embedded FBG can measure the strain inside a sandwich composite, but a gauge factor is required to measure the absolute strain experienced inside the composite. The temperature sensitivity of the embedded FBG is found to be close to that of the free space sensitivity of the FBG.The effect of the foam relaxation is also studied and it is found that foam relaxation can contribute to a strain error of ±16 µε in strain measurements during the observed time period in this study.

The results presented in this paper points to a direction that, embedded FBGs can be reliably used for strain measurement in sandwich composites and is less impacted by the thermal expansion of the composite laminate which is an advantage compared to other types of composite laminates. Further studies are required to estimate the FBG gauge factor for strain measurements and also to quantify the foam relaxation error based on an applied load. P89/Paper 9157-393

A flexible tactile sensitive sheet using a hetero-core fiber optic sensor Shuuhei Fujino, Hiroshi Yamazaki, A. Hosoki, K. Watanabe, Soka Univ. (Japan)

We have designed a tactile sensitive sheet based on a hetero-core fiber-optic sensor, which realize an areal sensing by using single sensor potion in one optical fiber line. Recently, flexible and wide-area tactile sensing technology is expected to applied to acquired biological information in living space and robot achieve long-term care services. The proposed tactile sensitive sheet shows monotonic responses on the whole sheet surface although different sensitivity by the position is observed at the sensitive sheet surface. In conclusion, the flexible material could be given to the tactile sensation which is attached under proposed sensitive sheet. P90/Paper 9157-429

Stabilization of fiber Bragg grating laser sensor with polarization scrambling Hyunjin Kim, Dae-gil Kim, Minho Song, Chonbuk National Univ. (Korea, Republic of)

We propose a fiber Bragg grating laser sensor system for possible uses in large scale wind turbine blades’ condition monitoring. The measurement instability due to the sensitive multi-wavelength lasing has been greatly improved by employing a polarization scrambling in the lasing cavity and a spectrometer demodulator. With suggested technique, we obtained 100% of data acquisition rate from all the 4 FBG laser sensors along single fiber-optic cable. Also the noise characteristics of the sensor outputs have improved 4 times more than the previous system. P91/Paper 9157-452

Dynamic measurement of inside strain distributions in adhesively bonded joints by embedded fiber Bragg grating sensor Hideaki Murayama, Xiaoguang Ning, Kazuro Kageyama, Daichi Wada, The Univ. of Tokyo (Japan); Hirotaka Igawa, Japan Aerospace Exploration Agency (Japan)

Fiber Bragg grating (FBG) with the length of about 100 mm was embedded onto the surface of a carbon fiber reinforced plastics (CFRP) substrate and two CFRP adherends were joined by adhesive to form an adhesive bonded single-lap joint. The joint was subjected to 0.5 Hz cyclic tensile load and longitudinal strain distributions along FBG were measured at 5 Hz by the fiber-optic distributed sensing system based on optical frequency domain reflectometry (OFDR). We could successfully monitor the strain distributions accurately with high spatial resolution of around 1 mm. P92/Paper 9157-528

In-situ Measurements with Fibre Bragg Gratings embedded in Stainless Steel Dirk Havermann, William N. MacPherson, Robert R. J. Maier, Duncan P. Hand, Heriot-Watt Univ. (United Kingdom)

Metal clad single mode optical fibres containing high reflectivity Bragg gratings are successfully embedded into stainless steel components using bespoke laser based additive manufacturing technology. Temperature cycling of the embedded sensor demonstrates the ability of gratings to survive the embedding process, and act as temperature or strain sensors. At extreme temperatures up to 500 °C, discontinuities in the gratings response are observed and these have been attributed to possible delamination issues at the interface between glass fiber and the surrounding metal. P93/Paper 9157-536

Fiber Bragg grating sensors for steel wire monitoring in real-time Jan C. Koch, Fraunhofer-Institut für Nachrichtentechnik Heinrich-Hertz-Institut (Germany), Clausthal Univ. of Technology (Germany); Martin Angelmahr, Fraunhofer-Institut für Nachrichtentechnik Heinrich-Hertz-Institut (Germany); Wolfgang Schade, Fraunhofer-Institut für Nachrichtentechnik Heinrich-Hertz-Institut (Germany), Clausthal Univ. of Technology (Germany)

Steel wires are widely applied in industrial applications - in most cases as critical components fulfilling high safety requirements in harsh environments (e.g. dockside cranes). In this paper a technique for real-time monitoring of steel ropes applying optical strain sensors based on fiber Bragg gratings is presented. The optical sensors are integrated within the wire strand and replace the core. The strain transmission from the outer wires to the sensors is assured by the mechanical coupling between the optical fiber and the strand. The actual strain load and rope vibrations in the kilohertz range can be determined in real-time. P94/Paper 9157-564

Fiber Bragg grating spectral features for structural health monitoring of composite structures Sean Webb, Kara J. Peters, Mohammed Zikry, North Carolina State Univ. (United States); Nikola Stan, Spencer Chadderdon, Richard Selfridge, Stephen Schultz, Brigham Young Univ. (United States)

We demonstrate the measurement of and applications for reflected spectral signatures obtained from FBG sensors in dynamic environments. Three uses of the spectral distortion measurements for monitoring of airframe structures are presented: the

measurement of the dynamic response of a laminated plate to an impact event; the measurement of damage induced spectral distortion in a thin plate during vibration loading; and the measurement of the change in dynamic response of an adhesively bonded joint with the progression of fatigue damage. P95/Paper 9157-573

Fibre optic humidity sensor designed for highly alkaline environments Kort Bremer, Merve Wollweber, Hannoversches Zentrum für Optische Technologien (Germany); Gerald Werner, Fibotec Fiberoptics GmbH (Germany); Tong Sun, Kenneth T. V. Grattan, City Univ. London (United Kingdom); Bernhard Roth, Hannoversches Zentrum für Optische Technologien (Germany)

This paper presents the design of a sensor packaging for a Fibre Bragg Grating (FBG) based fibre optic humidity sensor. The evaluation of the developed fibre optic sensor was performed under experimental conditions and verified its capability to withstand highly alkaline environments. Therefore, the sensor can be applied to monitor the concrete humidity level and thus to indicate the maintenance of concrete structures. P96/Paper 9157-578

Comparison of three different configurations of an optical sensor for tip-clearance measurements in turbines Iker Garcia, Joseba Zubia,aia Berganza, Univ. del País Vasco (Spain); Josu Beloki, Aeronautical Technologies Ctr. (Spain); Javier Mateo, Univ. de Zaragoza (Spain); Carmen Vazquez, Univ. Carlos III de Madrid (Spain)

The influence of the tip clearance on the performance of rotating turbo machinery is well known. The objective of this work was to measure this parameter using a non-contact sensor with a precision of 30 µm in a real turbine. An optical sensor whose main component is a bundle of optical fibers was selected to carry out the measurements. Three different configurations of the sensor have been tested by taking measurements on two distinct turbines. Tip-clearance measurements are achieved with the desired precision, providing the opportunity to develop applications related to structural health monitoring or active clearance-control systems. P97/Paper 9157-583

Deformation monitoring in prestressing tendons using fibre Bragg gratings encapsulated in metallic packages Grzegorz Fusiek, Marcus Perry, Pawel Niewczas, Univ. of Strathclyde (United Kingdom); Michael Johnston, EDF Energy (United Kingdom)

An investigation into the capability of deformation monitoring using fibre Bragg gratings encapsulated in metallic packages is presented in the paper. The proposed approach relies on a grating inscription into a metal coated fibre and brazing the fibre into a metal capillary using induction heating. A metal rod instrumented with encapsulated FBG strain and temperature sensors is placed in an electromechanical tester and stressed up 80 % of its ultimate tensile strength. It is demonstrated through a 60 h experiment that the sensors are capable of real-time deformation monitoring. P98/Paper 9157-617

Coating process of Fiber Bragg Grating sensors for SHM applications in metallic structures Enrique Piñeiro Ben, Tania Grandal, Alberto Asensio, Francisco Rodriguez, AIMEN - Asociación de Investigación Metalúrgica del Noroeste (Spain)

Embedded fiber optic sensors into composites have been studied for a long time, but embedding a fiber sensor into metallic structure is beginning to study. Recently, this has raised interest due to embedded FBG in the metallic structure provide capabilities for controlling parameters of the structural health status and also information about their own process of deterioration. In this paper we study three different techniques for coating a FBG sensor: physical vapour deposition (PVD), electroless deposition and electroplating. This paper describes the experimental procedure for coating metallic fiber optic sensors and the optical characterization. P99/Paper 9157-22

An acoustic vibration sensor based on tapered triple cladding fiber Hui Xu, Fufei Pang, Shiqi Zhao, Zhenyi Chen, Tingyun Wang, Shanghai Univ. (China)

An acoustic vibration sensor is investigated and demonstrated by using a tapered triple cladding fiber (TCF). It is fabricated by tapering a length of 2 cm TCF which is spliced between two single mode fibers (SMF). The TCF consists of core, inner cladding, middle cladding and outer cladding. After the tapering process, this structure becomes a tapered coaxial fiber coupler which presents a periodic filtering transmission spectrum. The surrounding vibration perturbation can be directly demodulated by intensity detection of the transmission power at a particular wavelength. The experimental result shows that the maximum frequency response of 700 kHz is achieved. P100/Paper 9157-48

High sensitivity high temperature sensor based on SMS structure with large-core all-solid bandgap fiber as the multimode section

Marcos A. R. Franco, Alice L. S. Cruz, Valdir A. Serrão, Carmem L. Barbosa, Instituto de Estudos Avançados (Brazil)

A fiber optic interferometric device based on a singlemode-multimode-singlemode (SMS) structure is proposed as a high sensitive high temperature sensor. The multimode section (MMF) consists of a large-core all-solid photonic bandgap fiber (AS-PBF) with silica as the background material and germanium-doped silica at the high index regions. The numerical analyses were carried out by beam propagation method. The numerical results indicate a constant high temperature sensitivity of about -35 pm/oC over a large temperature range from 20'C to 930'C. P101/Paper 9157-63

Simulated Pitot tube designed to detect blockage by ice, volcanic dust, sand, insects and to clear it: phase 1 David A. Jackson, Univ. of Kent (United Kingdom)

The Pitot Tube (PT) is a key sensors for modern aircraft; based on two tubes one aligned with the direction of air velocity, the other orthogonal to it. The data from the tubes is converted to air speed. If either tube is blocked the airspeed reading will be false potentially resulting in a fatal accident. A simple optical fibre sensor has been developed to detect tube blockage and is combined with a FBG temperature sensor to detect ice, these sensors control activators which removes the ice. Dust and sand can be removed by the intensity sensor activating a pressure flow P102/Paper 9157-119

Simultaneous measurement of strain and temperature using a unique LPG-coupled fibre laser scheme Daniel Leandro González, Univ. Pública de Navarra (Spain); Martins, City Univ. London (United Kingdom); Manuel Lopez-Amo, Univ. Pública de Navarra (Spain); Tong Sun, Kenneth T. V. Grattan, City Univ. London (United Kingdom)

In this work, we present and demonstrate a novel sensor system for simultaneous measurement of strain and temperature through a unique combination of a long period grating (LPG) and a fibre laser based on a fibre Bragg grating (FBG). In order to achieve this, a new erbium doped fibre laser (EDFL) structure is created, showing an optical signal-to-noise ratio (OSNR) of 55 dB and a peak power between -5 and 0 dBm. The strain and the temperature variation applied on the FBG and the LPG can be monitored through both the fibre laser wavelength shift and the change of the power level of a unique emission line, both showing a clear linear behaviour. P103/Paper 9157-121

Tuning the SMS spectrum based on UV radiation Di Zhong, Ye Tian, Jianzhong Zhang, Weimin Sun, Libo Yuan, Harbin Engineering Univ. (China)

We propose a fine spectrum-tuning scheme of the single-multi-single mode fiber (SMS) structure, realised by using UV radiation to modify the propagation constants of different modes in Multi-mode fiber of SMS. The primary experiments also demonstrated. It expect to have applications in the design of SMS based optical filters and sensors.

P104/Paper 9157-135

Interferometric displacement sensor by use of a single-passband incoherent microwave photonics filter Carlos R. Fernandez-Pousa, Haroldo Maestre, Pablo Corral, Univ. Miguel Hernández de Elche (Spain)

A novel interferometer interrogation concept based on Microwave Photonics is proposed and demonstrated. The system is conceptually equivalent to the double-interferometer interrogation technique in low-coherence interferometry, and similar to a Microwave Photonics filter based on a fiber-optics dispersive link driven by a sliced broadband source, where the resonance in its frequency response determines the interferometer’s optical path difference. In a proof-of-concept experiment, we use the interferometer as a displacement sensor, attaining a resolution of 63 microns over a measurement range of 3.7 mm using conventional 20-nm C-band EDFA sources and a radio-frequency bandwidth of 7 GHz.

P105/Paper 9157-137

Fiber powered sensing system for a long reach single mode fiber link and non-continuous applications Joao B. Rosolem, Fabio R. Bassan, Fernando R. Pereira, Rivael S. Penze, Ariovaldo A. Leonardi, CPqD (Brazil); Carlos Alexandre M. Nascimento, CEMIG Distribution (Brazil)

This work describes a non-continuous sensor operating technique in order to achieve a long reach sensing system, using power over fiber (PoF) in single mode fiber (SMF). Due to the use of super-capacitors and logical circuits in the sensor unit, the energy provided by PoF can be stored and used in an appropriated time. We demonstrated this approach with a micro video camera sensor powered by a 4.4-km SMF link in laboratory and by a 1.6-km link using optical ground wire cable (OPWG), installed between an electrical power substation and a tower of 138-kV overhead transmission line (OTL).

P106/Paper 9157-145

1×N optical fiber coupler based on a polyhedral gradient index lens Yuanhong Yang, Wen Dai, Kuiyan Song, BeiHang Univ. (China); Wei Jin, The Hong Kong Polytechnic Univ. (Hong Kong, China), BeiHang Univ. (China)

A method for building a 1×N fiber coupler based on a single polyhedral gradient-index lens (p-GRIN) is proposed. One end of the p-GRIN has polyhedral convex cone shape with N surfaces and is used as the light input port, while the other end is flat and used as the output port. When light from a single mode optical fiber illuminates the input end of the p-GRIN, N spatially separated light beams are generated at the output end and coupled respectively into N different output fibers. Results obtained from ray-tracing agree well with simulation results from the ZEMAX software. The output beam positions and light coupling efficiency to optical fibers could be optimized by adjusting the input cone angle and the distance between input fiber end and cone tip. This method may be adapted for any type of optical fibers and provide a practical solution for light coupling between single- and multi-core fibers.

P107/Paper 9157-156

Characterisation of effective mode-field diameter of coupled multi-core fibre Kazuhide Nakajima, Kotaro Saito, Yukihiro Goto, Chisato Fukai, Toshio Kurashima, Nippon Telegraph and Telephone Corp. (Japan)

We experimentally investigate the effective mode-field diameter (MFD) of coupled multi-core fibres (MCFs). The effective MFDs of two different coupled MCFs are derived by considering the relationship with the splice loss characteristics. We also examine the applicability of conventional variable aperture (VA) and far-field pattern (FFP) scanning methods by comparing with the effective MFD values. Our results show the potential of the VA method for evaluating the effective MFD characteristics of a coupled MCF with an arbitrary field distribution.

P108/Paper 9157-172

Design for a new fiber optic interferometer of water cut meter in oil well logging Ying Shang, Laser Institute of Shandong Academy of Sciences (China); Xiao-Hui Liu, Chang Wang, Shandong Academy of Sciences (China); Wen-an Zhao, Wuhan Univ. of Technology (China)

A new type of water cut meter based on fiber optic interferometer is proposed, sound pressure signal on the pipe is generated when the acoustic wave is propagated in a mixture of the pipe, the fiber optic sensors wrapped closely around the outside wall of pipe is capable of sensing sound pressure signal, the use of phase-carrier technology aloud sound velocity is solved out through the method of Phase Generated Carrier(PGC)and sound pressure spectrum, then water cut can be solved according to the relationship between sound velocity and water cut.

P109/Paper 9157-173

First observation of fiber fuse phenomenon in polymer optical fibers Yosuke Mizuno, Neisei Hayashi, Hiroki Tanaka, Kentaro Nakamura, Tokyo Institute of Technology (Japan); Shin-ichi Todoroki, National Institute for Materials Science (Japan)

We report the first observation of the fiber fuse in POFs. A fuse propagation velocity of 21.9 mm/s, which is 1–2 orders of magnitude slower than that in standard silica fibers, is experimentally demonstrated. The achieved threshold power density and proportionality constant between the propagation velocity and the power density are 1/180 of and 17 times the values for silica fibers, respectively. An oscillatory continuous curve instead of periodic voids is formed after the passage of the fuse. An easy fuse termination method is also presented. These results are significant in developing POF-Brillouin-based distributed strain/temperature sensors.

P110/Paper 9157-186

Viscoelastic tuning of fibre Bragg gratings during regeneration John Canning, The Univ. of Sydney (Australia); Sharoui Gao, The Univ. of Sydney (Australia), Zhejiang Univ. (China); Kevin Cook, Arnaud Loubert, The Univ. of Sydney (Australia); Matthieu Lancry, Univ. de Paris Sud (France)

Regenerating at constant temperature under load allows inelastic changes in glass that can be exploited to tune the Bragg wavelength of a filter to any arbitrary spectral position. We have reported > 20nm of tuning of a 1 cm grating with no limit in sight. Further, regenerating under a temperature profile allows complex spectral shaping of the grating profile. As an example, we have reported broadband chirping by > 9 nm over 1 cm using this approach. High temperature viscoelastic tuning therefore offers a simple and powerful low cost way of tuning the properties of fibre Bragg gratings using a single phase mask.

P111/Paper 9157-189

High-stability double-pass backward erbium-doped superfluorescent photonic crystal fiber source Shuangchen Ruan, Xu Wu, Cheng-xiang Liu, Li Zhang, Shenzhen Univ. (China)

A high-stability erbium-doped superfluorescent photonic crystal fiber source (SPCFS) is presented. Optimization of the high-stable SPCFS is achieved by combining high-performance EDPCF, optimal fiber length, and source structure with suitable pump power. The result shows a 56.979 ppm mean wavelength stability of a prototype SPCFS is demonstrated with the temperature varied in the range of −40 °C—70 °C. Especially, in the room temperature, the mean wavelength stability of a prototype SPCFS is less than 2.59 ppm, the total output power stability is less than 0.021%, which will be approaching the requirement for inertial-grade fiber optic gyroscopes.

P112/Paper 9157-515

Real time fast and distributed measurement of a Brillouin-inhomogeneous fiber using frequency-tailored probe in slope-assisted BOTDA Orr Danon, Moshe Tur, Tel Aviv Univ. (Israel)

We present a truly distributed tailored-probe SA-BOTDA measurement. The measurement is performed on an inhomogeneous fiber, with static strain which linearly varies along the fiber and exceeds the classical constant-frequency probe SA-BOTDA method dynamic

range. The measurement is compared against a classical constant-frequency probe measurement and is shown to have a superior dynamic range.

Friday 6 June

Session 12: Sensor Application and New Techniques Friday 6 June 2014 9:00 AM - 10:00 AM Session Chairs: Minghong Yang, Wuhan University of Technology (China) Gilberto Brambilla, Univ. of Southampton (United Kingdom) Time: 9:00 - 9:30; Invited Paper 9157-683

Next generation of optical fibre sensors: new concepts and perspectives Luc Thévenaz, Ecole Polytechnique Fédérale de Lausanne (Switzerland)

Fibre sensing has reached an interesting turning point today: a clearer assessment about promises that were really held and those that failed to convince can be envisioned. A choice of key fibre sensing techniques will be reviewed and a critical discussion about their real impact will be presented. The promising potentialities of distributed sensing in its different flavours will be addressed, without omitting perspectives on other major techniques, such as fibre gyros, Bragg gratings and chemical sensors. Time: 9:30 - 9:45; Paper 9157-490

Microwave photonics filtering technique for interrogating long weak fiber Bragg grating sensors Amelia L. Ricchiuti, David Barrera, Salvador Sales, Univ. Politècnica de València (Spain); Luc Thévenaz, Ecole Polytechnique Fédérale de Lausanne (Switzerland); José Capmany, Univ. Politècnica de València (Spain)

A system to interrogate photonic sensors based on long weak fiber Bragg gratings (FBGs) is presented and experimentally demonstrated, dedicated to measure the precise location of several spot events. The principle of operation is based on a technique used to analyze microwave photonics (MWP) filters. The long weak FBGs are used as quasi-distributed sensors. Several events can be detected along the FBG device with a spatial accuracy under 1 mm using a modulator and a photo-detector (PD) with a modest bandwidth of less than 500 MHz. The simple proposed scheme is intrinsically robust against environmental changes and easy to reconfigure.

Time: 9:45 - 10:00; Paper 9157-545

Palladium coated ball lens for optical fibre refractometry based hydrogen sensing Sahar A. Chowdhury, Jane Hodgkinson, Ralph P. Tatam, Cranfield Univ. (United Kingdom); Ben J. S. Jones, AWE plc (United Kingdom)

An optical fibre refractometer using a ball lens as a sensor head has been developed and characterised. Light from a superluminescent diode is directed to an optical fibre sensor head and the intensity of the returned beam gives a measure of the refractive index of the medium at the ball lens fibre tip. A second beam is used to reference the intensity measurements. The system is capable of detecting changes in refractive index with a resolution of 0.003 RIU. The ball lenses have been coated with an 80nm thick layer of palladium and the potential use of this system as a micromirror hydrogen sensor is demonstrated. This technique offers a simple sensor head arrangement, with a large signal sampling area compared with that of a bare fibre.

Time: 10:00 - 10:15; Paper 9157-619

Advanced photonic vortex flowmeter with interferometer sensor for measurement of wide dynamic range of medium velocity at high temperature and high pressure Henrik Krisch, Krohne Messtechnik GmbH (Germany), Commissariat à l'Energie Atomique (); Benedikt Niermann, Ali Gedikli, Krohne Innovation GmbH (Germany), Commissariat à l'Energie Atomique (); Tadeusz Tenderenda, Tomasz Nasiłowski, Military Univ. of Technology (Poland), InPhoTech Ltd. (Poland)

The paper presents a new solution of flowmeter to measure the flowing medium velocity using fiber sensing methods. A Mach-Zehnder interferometer is implemented for the detection of vortices [1] [2]. The measurement of flow is based on the vortex frequency detection of a vibrating diaphragm placed in an optimized measuring chamber. The stress of the vibrating diaphragm is measured with use of a Mach-Zehnder (MZ) fiber interferometer whose fiber arms are fixed with the diaphragm. This solution allows for measuring flow of liquids, gases and vapors in the temperature range of -200°C to +550°C and pressures up to 300 bar.

Time: 10:15 - 10:30; Paper 9157-672

Vibration sensor based on highly birefringent Bragg gratings written in standard optical fiber by a femtosecond laser

Karima Chah, Damien Kinet, Christophe Caucheteur, Cédric Chluda, Patrice Mégret, Marc Wuilpart, Univ. de Mons (Belgium)

We present a vibration sensor based on highly birefringent fiber Bragg gratings written in standard single mode optical fiber and realized with UV femtosecond pulses. This vibration sensor takes advantage of the stress-induced phase shift between the two orthogonally polarized fiber eigenmodes which induce intensity distribution changes in the two fiber Bragg grating reflection modes. The gratings are inscribed with the femtosecond line by line technique and have a birefringence value of 6 10-4. We demonstrate that theses gratings are temperature birefringence insensitive and ideal for vibration measurements.

Coffee Break 10:30 AM - 11:00 AM

Session 13: Postdeadline Papers (6 papers)

Friday 6 June 2014 11:00 AM - 12:12 PM

Session Chairs: John Canning, The Univ. of Sydney (Australia);

Jose Luis Fabris, Federal University of Technology, (Brazil)

Session 14: Closing OFS23 Remarks and Announcing OFS24

Friday 6 June 2014 12:15 PM - 13:00 PM Chairs: José Miguel López-Higuera, University of Cantabria, Spain Hypolito José Kalinowski; Federal University of Technology, Paraná, Brazil OFS23 Closing Lunch / Comida de Clausura 13:00 PM - 15:00PM

Key of First Authors

A

Abd Aziz, Aiman

Alcusa-Sáez Erica

Alem, Mehdi

Algorri, J. Francisco

Allsop, Thomas

Ames, Gregory

Andre, Ricardo

Arkwright, John

Ascorbe, Joaquin

Avino, Saverio

B

Baitinger, Eugen

Baker, Chams

Baldwin, Christopher

Barrera-Villar, David

Basic, Petar

Becker, Martin

Bergman, Arik

Berruti, Gaia Maria

Bhowmik, Kishore

Biswas, Palas

Blake, Jim

Bocciolone, Marco

Boldyreva, Ekaterina

Bolognini, Gabriele

Bos, Joseph

Bravo Acha, Mikel

Bremer, Kort

Bressel, Lena

Búa-Núñez, Iago

Bueno, Antonio

Butov, Oleg

Bykov, Dmitry

C

Cangialosi, Chiara

Canning, John

Cao, Chunyan

Cao, Yingchun

Cao, Yulong

Carvalho, Lidia

Cennamo, Nunzio

Chah, Karima

Chamoun, Jacob

Chen, Nan-Kuang

Chen, Y.

Chen, Zhihao

Chenari, Zeinab

Cheng, Linghao

Chiavaioli, Francesco

Chiniforooshan, Yasser

Chiuchiolo, Antonella

Chowdhury, Sahar

Chu, Fenghong

Cohen, Raphael

Consales, Marco

Correia, Ricardo

Cotillard, Romain

Cubillas, Ana

D

da Silva, Gleison

Dai, Yu-Tang

Danon, Orr

de Nazaré, Fábio

De Pauw, Ben

Delgado-Pinar, Martina

Deng, Hongchang

Deng, Ming

Diaz, Silvia

Ding, Ming

Ding, Mingjie

Domingues, Maria

Dominguez-Lopez, Alejandro

Dong, Yongkang

Du, Jiangbing

Duan, Ning

durana, gaizka

E

Eftimov, Tinko

Elooz, David

Elsmann, Tino

Eom, JongHyun

Ertman, Slawomir

F

Ferdinand, Pierre

Fernandes, Pedro

Fernandez-Pousa, Carlos

Ferreira, Marta

Ferreira, Ricardo

Fiorin, Rodrigo

Franco, Marcos A.

Frignet, B.

Frosch, Torsten

Fujino, Shuuhei

Fusiek, Grzegorz

G

Gabai, Haniel

Gallego, Daniel

Gan, Huanbiao

Garcia, Iker

Garcia-Souto, Jose

Gúemes, Alfredo

Geernaert, Thomas

Gray, Malcolm

Guan, Chunying

Guo, Tuan

Gyger, Flavien

H

Habel, Wolfgang

Habisreuther, Tobias

Haneef, Shahna

Hao, Gengjie

Havermann, Dirk

Hayashi, Neisei

He, Qian

Helminger, Dominik

Henderek, Vince

Herman, Peter

Holdynski, Zbigniew

Hong, Jun Gi

Honthaas, Joachin

Hotate, Kazuo

Huang, Wenzhu

I

Iadicicco, Agostino

Iida, Daisuke

J

Jackson, David

Jang, Kyoung Won

Jeong, Ji Ho

Jin, Wa

Jones, Julian D.

Jones, Kevin

K

Karam, Leandro

Kavungal, Vishnu

Kawano, Marianne

Kersey, Alan

Kim, Hyunjin

Kim, Jin-Hyuk

Kim, Sung-Jae

Kim, Yong Hyun

Kito, Chihiro

Ko, Myeong Ock

Koba, Marcin

Koch, Jan

Korposh, Serhiy

Kostecki, Roman

Kostritskii, Sergey

Krisch, Henrik

Kwon, Oh-Jang

L

Launay, François-Xavier

Layeghi, Azam

Le Floch, Sébastien

Leandro González, Daniel

Ledermann, Christoph

Lee, Byoungho

Lee, Graham C.

Lee, Hwidon

Leite, Ivo

Li, Jie

Li, Jin

Li, Jun

Li, Shuqiang

Li, Wenhai

Li, Yaowen

Liang, Yizhi

Liao, Changrui

Lieberman, Robert A.

Liehr, Sascha

Lin, Guei

Liu, Fu

Liu, Jianxia

Liu, Qin

Liu, Zhengyong

Lomer, Mauro

López-Gil, Alexia

Lu, Mifang

Lu, Ping

Lu, Xin

Luo, Haipeng

M

Ma, Jun

Maier, Robert

Malara, Pietro

Manders, Mark

Marin, Gabriela

Marques, Leonel

Martins, Hugo

Martins, Raquel

Masoudi, Ali

Matsumoto, Tsuyoshi

Matsuoka, Ora

Melo, Luis

Mendez, Alexis

Mendoza, Edgar

Miao, Yinping

Michalak, Bartosz

Mikhailov, Vitaly

Minakawa, Kazunari

Minakuchi, Shu

Minardo, Aldo

Mizuno, Yosuke

Mizutani, Tadahito

Moayyed, Hamed

Molin, Stéphanie

Montero, David

Morana, Adriana

Muanenda, Yonas

Müller Georg

Munzke, Dorit

Murayama, Hideaki

N

Naeem, Khurram

Nakajima, Kazuhide

Napierala, Marek

Nascimento, Ivo

Nazari, Marziyeh

Nguyen, Linh

Ni, Haibin

Nikbakht, Hamed

Nishiyama, Michiko

Nuño, Javier

O

Oliveira, Ricardo

Omichi, Koji

Osório, Jonas

P

Palmieri, Luca

Pan, Zhengqing

Park, SeongJun

Parker, Tom

Passos, Daniel

Pechstedt, Ralf

Peng, Feng

Perez-Herrera, Rosa Ana

Petrovich, Marco

Piñeiro Ben, Enrique

Pinto, Ana M.

Poeggel, Sven

Polz, Leonhard

Popov, Alexander

Popp, Juergen

Preter, Eyal

Pulido, C.

Pura, Paulina

Q

Qiu, Tiequn

Quintela, Antonio

R

Rajan, Ginu

Ran, Yang

Rao, Yunjiang

Real, Eusebio

Reyes-Vera, Erick

Ricchiuti, Amelia

Rigas, Evangelos

Rivero, Pedro

Rocco Giraldi, Maria Thereza

Rodrigues Ribeiro, Ana Rita

Rodriguez-Cobo, Luis

Rogers, Dan

Rohwetter, Philipp

Roriz, Paulo

Rosolem, Joao

Rota-Rodrigo, Sergio

Ruan, Shuangchen

S

Sánchez Martín, José Antonio

Sadeghi, Jalal

Sakamoto, Akira

Santos, Diego

Sasaki, Kin'ichi

Schartner, Erik

Schilder, Constanze

Schmidt, Markus

Schneller, Oliver

Semenova, Yuliya

Shafir, Ehud

Shang, Ying

Shao, Li-Yang

Shi, Leilei

Shiloh, Lihi

Shim, Young Bo

Shlomovits, Omer

Shlyagin, Mikhail

Signorini, Alessandro

Sikali-Mamdem, Yolande

Silva, Susana

Smietana, Mateusz

Socorro, Abian

Soto, Marcelo

Stańczyk, Tomasz

Steffen, Milan

Sulejmani, Sanne

Sun, dandan

Sun, Lipeng

Sun, Qizhen

Sun, Zhongyuan

T

Takubo, Yuya

Tan, Dongjie

Tan, Y. C.

Tanaka, Satoshi

Tapetado Moraleda, Alberto

Tekuramori, Shingo

Tenderenda, Tadeusz

Thévenaz, Luc

Tian, Zhengwen

Tosi, Daniele

Tsiminis, Georgios

U

Uchimura, Ryotaro

Urricelqui, Javier

Ushakov, Nikolai

V

Villatoro, Joel

Villnow, Michael

Viveiros, Duarte

Voskoboinik, Asher

Vukovic, Natasha

W

Wada, Daichi

Waltermann, Christian

Wang, Chao

Wang, Fang

Wang, Fuyin

Wang, Jing

Wang, Pengfei

Wang, Ruohui

Wang, Yao

Wang, Yiping

Warren-Smith, Stephen

Webb, Sean

Wen, Jianxiang

Willsch, Michael

Woliński, Tomasz

Woschitz, Helmut

Woulfe, Peter

Wren, Stephen

Wu, Chuang

Wu, Huijuan

Wu, Qiang

Wu, Yu

X

Xu, Bo

Xu, Dan

Xu, Fei

Xu, Hui

Xu, Yanping

Xu, Zhilin

Y

Yamashita, Rodrigo

Yamashita, Shinji

Yamazaki, Hiroshi

Yan, Di

Yan, Zhijun

Yang, Fan

Yang, Jingyi

Yang, Shuo

Yang, Yuanhong

Yang, Zhisheng

Yao, Bai-Cheng

Yao, Yuan

Yin, Guolu

Yin, Zhen

Yoo, Wook Jae

Yoon, Min-Seok

Yuan, Jianying

Yuan, Tingting

Z

Zaidi, Syed Farhan Haider

Zamarreño, Carlos

Zawawi, Mohd Anwar

Zhang, Faxiang

Zhang, Qiang

Zhang, Wei

Zhang, Weili

Zhang, Wentao

Zhang, Yaxun

Zhang, Yu

Zhao, Yunhe

Zheng, Yu

Zhong, Di

Zhou, Ai

Zhou, Bochao

Zhou, Wenjun

Zhu, Jiali

Zibaii, Mohammad Ismail

Zubiate, Pablo

SOCIAL PROGRAM Welcome Cultural Event / Live Music Concert Monday 2 June 2014 19:15 PM - 21:15 PM

Place: Hotel Santemar A Cantabria Folk Dance Show and an informal live music concert will be held in the Hotel Santemar. The former will be performed by the “Coros y Danzas de Santander” group and the latter by the “Green River Tribute” band performing music from the Creedence Clearwater Revival. Drinks will be provided.

Welcome Reception Tuesday 3 June 2014 19:15 PM - 21:15 PM

Place: Palacio de la Magdalena

An informal welcome reception will be held in the Magdalena Palace (the summer palace of the Kings of Spain at the beginning of the XX century). Drinks and a light buffet will be provided (courtesy of the Santander City Council).

Conference Tour Wednesday 4 June 2014 19:15 PM - 21:15 PM

Place: Bay of Santander

An exceptional view of Santander from the sea will be enjoyed during the guided boat tour across the city bay. A Tourist Guide, speaking in English, will be provided to illustrate the tour. A bus service will be provided (from the Santemar Hotel) at 18:45 to arrive at the tour meeting point.

“De pinchos por Santander” Program Wednesday 4 June 2014 21:00 PM - 24:00 PM

Place: Rio de la Pila

After the tour you may enjoy some free time to visit the Santander City Centre (that is very close to the arrival point of the Conference Tour). You may also enjoy the special “de Pinchos por Santander” Program by tasting small plates of the Spanish Gastronomy (tapas) and drinks at special prizes along one of the most popular areas of Santander. A street-live music program will be provided around the area (courtesy of the Santander City Council). Please check the leaflet inside the conference Bag. Return to the conference hotel is for your own account.

Conference Gala Dinner, Awards Ceremony and Cultural Event Thursday 5 June 2014 19:15 PM - 23:30 PM

Place: Hotel Chiqui The Conference Gala Dinner will be held at Hotel Chiqui located at 15minutes (on foot) from the Conference Hotel. The evening will start (at 19:15) with a “Family OFS23 Photo” followed with a welcome cocktail with “tapas”. Then (at 20:15) the conference dinner will be served. At 21:45 hours you will enjoy a typical Spanish “Flamenco Show” performed by the “Paula Rodriguez” group. The Awards Ceremony will start at 22:00. Finaly (at 22:30) a “world wide popular music tour” will be performed for the OFS23 by “The Fronterizos”, band leaded by Marcos Bárcena. Further information will be provided at the OFS23 website. Other Social Facilities: Accompanying Persons Program For attendees who have the opportunity to bring their partners to the OFS23 Conference, the travel agency “Viajes el Corte Ingles” will offer several optional excursions that you can check below. If you are interested you should contact directly the travel agency and book in advance your excursions (no later than May 28, 2014). Please notice that seats are limited. In addition, a minimum number of participants will be required and, if this limit is not reached for a specific option, the money will be refunded. EXCURSIONS OFFERED by the Viajes el Corte Ingles travel agency: JUNE 03, 2014 – FULL DAY – MINIMUM NUMBER: 50 PARTICIPANTS On June 03 (during the morning) there will be an excursion to San Vicente de la Barquera, Comillas and Santillana del Mar, one of the most attractive historical and touristic places in the region of Cantabria. A bus will depart from Hotel Santemar at 09:00 AM and come back at 06:00 PM. The price is 52 euros and the tour includes the bus, the official guide with a guided tour in the villages and lunch buffet in a Hotel in Santillana del Mar. JUNE 04, 2014 – FULL DAY – MINIMUM NUMBER: 50 PARTICIPANTS On June 04 there will be an excursion to The Nature Park Cabárceno. This is not a conventional zoo or a Natural Park. It is a space naturalized by the hand of man, from the primitive beauty of a landscape of 750 hectares. The Nature Park Cabarceno welcomes hundreds of animal species from five continents in semi-liberty, spread over large surfaces. A bus will depart from Hotel Santemar at 10:00 AM and come back at 06:00 PM. The price is 60 euros and the tour includes the bus, the official guide in the park, ticket, and tipical lunch in the Park Cabarceno. JUNE 06, 2014 - MINIMUM NUMBER: 50 PARTICIPANTS In the afternoon, June 06, there will be an excursion to The National Museum of Altamira. The Cave of Altamira was declared a World Heritage Site (UNESCO) in 1985. The Museum offers all its visitors a permanent exhibition, guided tours of the Neocave, children's workshops and experimental archaeology activities. More details in the OFS23 website.

ADITIONAL USEFUL INFORMATION

Venue The Twenty-third International Conference on Optical Fibre Sensors (OFS23) will be held on the Hotel Santemar from Monday 2 June to Friday 6 June 2014.

Conference Registration Registration will be held in OFS23 Registration Desk placed at the Hotel Lobby. In general the registration will be open from 16:00 PM to 18:00 PM on Sunday June 1, 2014 and from (8:00 AM to 12:00 AM) from Monday 2 to Friday 6 of 2014. Please see the OFS23 General Schedule at a Glance at the beginning of this booklet and/or the OFS23 website. You can also download a floor plan and directions from the OFS23 website. On arrival, you will receive a registration pack containing conference material and a lapel badge. Please wear your badge at all times to allow you entry to the exhibition area, conference sessions etc. and help with security. Replacement badges can be issued at the registration desk.

Internet Access Free Wireless Access will be available for all OFS23 attendees in the whole Conference Hotel. Login details will be provided at the conference and hotel reception desk. The conference venue will also have a small number of PC’s with internet access available for your use.

Oral Presentations The Technical Oral sessions will be held in the Convencion Room. The lecture room is equipped with the following audio-visual equipment: multimedia projector, PC / Laptop with PowerPoint and Adobe pdf facilities and Laser pointer.

Speakers are requested to bring their presentations in an USB memory stick and preload them onto the PC located in the lecture room and/or the Confererence registration well in advance before their presentation (at the latest during the coffee break before the associated conference session). Speakers should save their presentation into the appropriate pre-named session folders on the desktop with file-names starting the speakers surname and initial. To optimise compatibility, particularly for the inclusion of multimedia components, PowerPoint presentations should have been saved using PowerPoint’s “Package for CD” facility.

We kindly request to use the computer available in the Conference Room to perform your presentation in order to avoid unnecessary delays.

The general file code must be used:

a) for plenary talks: PT X Y. X is the number of plenary talk and the Y is the surname of the speaker (e.g. for the second plenary talk: PT2 Hyun Yun)

b) for Special Session invited talks ITSSXY. X is the session number and the Y is the surname of the speaker (e.g. for the special session number III and first invited talk: ITSSIIIPop).

c) for Regular Invited Papers ITRXY. X is the session number and the Y is the surname of the speaker (e.g. for the regular session 12 invited talk: ITRS12Thevenaz).

d) For Oral Regular presentations: ORSXYZ. Where X is the session number and the Y is the number paper and Z is the surname of the speaker (e.g. for the Regular Session number 1 and first oral talk: ORS11Yun Ma).

The lecture theatre is reasonably large, and although several screens will be distributed through the room, speakers should use a minimum 15 point font size in PowerPoint slides to ensure legibility.

Presenters are requested to prepare their talks to match the allocated time slots which will be rigidly enforced by session chairs. Speakers for Invited Plenary talks should aim to speak for no more than 55 minutes with 5 minutes left for discussion. Presenters of invited papers should aim to speak for no more than 25 minutes with 5 minutes left for discussion, and for contributed presentations the associated time will be 12 minutes with 3 minutes left for discussion. The duration of postdealine paper presentations will be announced at the conference. However, tentatively it could be 10 minutes presentation plus 2 minutes for discussion.

Poster Presentations Posters will be displayed during the conference in areas A, B and C and at the times indicated in the Conference Programme. Area A (posters 1-32) will be located inside the Exhibition Room; Area B (posters 33-58) close to the Exhibition Room and area C (posters 59-112) will be located at the Hotel Japanese Garden (see Figure below).

Posters should be at maximum A0 in size with a portrait orientation (i.e., 1189 mm height by 841 mm width). Velcro will be provided for presenters to fix their posters to their boards. Presenters are requested to consult the Conference Programme to find the index number of their poster and the session where it will be displayed. Presenters should ensure that their poster is placed on the board showing the appropriate index number sufficiently in advance before the beginning of the specific session. In particular, posters should be placed on their associated boards before 11:00 AM of their corresponding Session (Tuesday, Wednesday or Thursday).

The presenter or a co-author should make themselves available at the poster location for the duration of the session. Authors are responsible for removing their posters at the end of their corresponding session. Poster Sessions (I, II and III) will take place from 17.00 to 18.30 on Tuesday 3, Wednesday 4 and Thursday 5 June, 2014 (respectively). Coffee and other drinks will be also served during the poster sessions.

You will find the following code in each poster panel, indicating the poster number (on the left), and the poster (its paper code, for example 9157 – 15 for Poster Session I: June 3) to be displayed each day (Poster Session I: June 3; Poster Session II: June 4 and Poster Session III: June 5).

Exhibition The Trade Exhibition (indissoluble part of OFS23) will be held in the Exhibition Area integrated by the hotel rooms Palma, Valencia, Murcia y Granada (configure as a single large room). The exhibition will be held from Tuesday 3 to Thursday 5, 2014. The opening hours are 10.00 AM to 12:30 PM and 14:00 PM to 18.30 PM. The Exhibition area will be ready for exhibitors to set up their stands and/or table-tops in the morning of 2th June, from 09:00 on. All stands should be completed by 10:30 am on 3th June for the Exhibition Opening. The exhibition will be closed out of the exhibition time. The exhibition will be also closed during lunchtime to allow the exhibition staff to have lunch All exhibitors will be responsible for picking up their material at the end of the Exhibition, and they should have their material picked up by Friday 6 at 12:30 PM. The list and location of the 33 exhibitors can be found at the end of this handbook.

OFS23 Journal Postpublication An IEEE/OSA Journal of Lightwave Technology Special Issue devoted to the 23rd International

Conference on OPTICAL FIBER SENSORS will be published. The Guest Editors (the Chairs of the

conference) and the Editor-in-Chief, encourage you to submit an extended version of your accepted

conference papers via the website: http://mc.manuscriptcentral.com/jlt-ieee. Deadline: 7 September,

2014.

Submission questions: Doug Hargis, Journal of Lightwave Technology d.hargis@ieee.org7 14

Additional Meeting / Business Room To contribute to the scientific, technical, project or business discussion, in addition to the Lobby and Japanese Garden an additional meeting room will be provided. For this pupose, the Salón Nixe near the Exhibition and the lecture areas will be provided with appropriate facilities. Coffe breaks will also be served in this room.

OFS23 Committee Meeting Room During the conference the OFS23 Conmitte Meetings will take place on the Room or Salón Saray. All thse meetings will take place from 12:30 PM to 14:00 PM. Meals will be served during the meetings. Tuesday 3, 2014: TPC meeting Wednesday 4, 2014: IHC meeting Thursday 5, 2014: ISC meeting

Coffee/Refreshments Breaks Coffee Breaks will be served in several areas during the Conference: at the access area to the Exhibition, in the Nixe Room and in the Hotel Japanese Garden.

Meals A buffet breakfast is included in the room price. It will be served at the Main Dining Room (Salon Arenas). Four meals (lunchs, 12:30 PM to 14:00 PM) will be served during the conference. During Tuesday 3, Wednesday 4 and Thursday 5, June they will be served in buffet service style. The closing conference special meal (on Friday 6) will be served in the table-service style. A special local drink will be served at the end of the meal. All meals will be served in two areas: Salon Arenas and the Hotel cafeteria area. Participants with requirements in terms of special diets are asked to notify the conference office by e-mail (ofs23@teisa.unican.es) before their arrival. For those with special diet requirements (e.g. gluten free) please make yourself known to the catering team. Unfortunately it will not be possible to provide an alternative menu unless prior notification has been received. Daily meal tickets and badge indentification will be necessary to access the different Conference services.

Messages A message board will be placed near the conference registration desk. Participants should check regularly for messages, as an attempt to locate participants during session times will only be made in case of emergency.

Local Taxis

Please contact the conference hotel reception desk for assistance. In any case you can ask for a taxi

dialing the phone number +34 942 33 33 33.

Very special fares to visit the region areas or to travel to/from the Bilbao airport are offered by the Varesina di Navigazione service. Please visit the OFS23 website for further information (http://www.teisa.unican.es/OFS23/index.php?option=com_content&view=article&id=73&Itemid=82) or contact direcly the company: varesinadinavigazione@yahoo.es / Phone | Fax: +34 942 36 56 80 / Mobile: +34 686 92 64 39

Complaints We hope that your time at the conference will be enjoyable. Should you encounter any problems during your stay please report them to the conference registration desk as soon as possible. The conference team will make every effort to rectify the issue.

Accidents or Emergency In the event of an emergency or accident please contact security services at the conference hotel who are on duty 24hrs a day or contact direcly with the registration Hotel Desk at the Lobby.

OFS23 Menus In the following you can find a detailed description of the menus to be offered during the conference. BASSIC BUFFET Cold section Assortment of mix lettuces (rocket, radiccio,...) Variety of crudittes to make your own salad (sweet corn, beetroot, carrot, bean sprouts, tomatoes, onion, olives, ..).. Dressings and sauces ( vinagrette, extra virgin olive oil, balsamic vinagrette, mayonaise, tartar sauce, cocktail sauce, ...) Cold meats (serrano ham, chorizo, salchichon) Manchego cheese Two diferent salads per day (pasta salad, rice salad, seafood salad, potato salad, caesar salad,...) Cold soup (gazpacho, salmorejo, vichysoise, beetroot, melon, ....) Hot section Starters ( vegetables panaché, stuffed peppers, colifower cheese,...) Soup of the day (fish soup, butternut squash, seasonal vegetables soup,...) On the side (croquets, fried squid, battered prawns,...) Chips Fish (hake, cod, sea-bass, sea-bream,...) Meat (roasted chicken, loin of pork, beef ragout,...) Dessert section Assortment of different desserts (creme caramel, custard, chocolate tarts, cheese cakes, chocolate brownies,...)

BUFFET 1: TUESDAY (JUNE 3, 2014) Bassic buffet + paella selection and panadera potatoes BUFFET 2: WEDNESDAY (JUNE 4, 2014) Bassic buffet + iberico ham, cheese board selection, one more elaborated salad, stew of the day (with beans with chorizo, tuna "marmita",...) BUFFET 3: THURSDAY (JUNE 5, 2014) Bassic buffet + pasta of the day, one more fish, one more meat GALA DINNER (June 5, 2014) The Conference Gala Dinner will take place at the Chiqui Hotel. Previously a welcome cocktail and “tapas” will be served. At the end of the dinner and during the cultural event a drink will be provided. The OFS23 Gala Dinner Menu will include: Welcome Cocktail Foie lolly - pop covered with white chocolate Smoked salmon and asparragus canapé Salmorejo cup Guacamole and clam bite Mushrooms and ham mini toast Home made mini croquettes Dinner Menu Iberian ham and foie salad with nuts Stewed anglerfish with mussels sauce Sellection of crusty lamb with risotto Puff pastry gateau and biscuit glacée with hot chocolate sauce Coffee and Spirits White wine LaFuente D.O. Rueda Red wine Crianza Viña Real D.O. Rioja

And additional drink will be server on the table at the beginning of the live concert.

OFS23 CLOSING LUNCH (June 6, 2014) This lunch will be served on table-service style. The menu will include:

Chicken drumstick and mushroom rissotto (finished with organic butter from Cantabria and Parmessan cheese) Hake in green sauce with clams Fried ice cream milk choice A special local drink will be also served at the end of the lunch.

Exhibitors

Nº Company Contact Person Description

1 OZ Optics Limited Gold Sponsor

Omur Sezerman CEO & President sales@ozoptics.com www.ozoptics.com

OZ Optics Limited is the leading company in developing fiber optic sensors. 2009 Frost & Sullivan Award Winning sensor generates and measures stimulated brillouin scattering in optical fibers to provide high-resolution simultaneous measurements of both strain and temperature along the entire length of the fiber. By wrapping or embedding a standard telecom singlemode fiber inside a structure such as an oil pipeline, power lines or dam, users can detect when and where the structure is being strained or heated and correct the problem before failure occurs. It is ideal for monitoring large structures including oil & gas pipelines, bridges, power lines, dams, and security fences. The sensor could also be used in detecting fire and corrosion/erosion.

2 Fibersensing Gold Sponsor

Maria Gonçalves info@fibersensing.com www.fibersensing.com

FiberSensing is a world leader in the development, production and installation of advanced monitoring systems based on optical fiber Bragg grating (FBG) sensor technology. The main markets are Civil and Geotechnical Engineering, Power Generation and Distribution, Wind, Aerospace and Railway and Transportation. The company offers a wide range of sensors, measurement units and software packages and provides complete solutions for monitoring

3 FBGS International N.V.

Mr. Nick Plescia plescia@fbgs.com www.fbgs.com

FBGS is a Belgium / Germany based developer and manufacturer of high strength Fiber Bragg Gratings (FBG) using draw tower technology, where the grating array is written during the drawing process of the fiber. This automated process results in very high quality, cost effective Fiber Bragg Gratings with unique characteristics. These are suitable for both standard and bespoke applications in industries such as: medical, composite, transport, process, civil & geo, telecom and R&D. FBGS supplies ‘Draw Tower Gratings’ - DTG® as an OEM component and our DTG® ‘s can today be found in many applications and products developed by our customers' worldwide

4 Fibercore Ltd. Gold Sponsor

José María Álvarez de Con jose.alvarez@fibercore.com www.fibercore.com

A World leader in the field of fiber optics, Fibercore supplies more PM, Er-doped and bend-insensitive single-mode fiber to more customers than any other fiber supplier in the World. Celebrating 30 years dedicated to the development of specialty optical fibers, we also offer rare-earth doped, photosensitive and cladding pump fibers.

5 Smart Fibres Ltd.

Chris Staveley chris.staveley@smartfibres.com www.smartfibres.com

Smart Fibres pioneered the development of fiber Bragg grating based monitoring systems and has been an industry leader for over 15 years. With a broad range of FBG fiber optic sensor and interrogator products and a wealth of applications knowledge, we serve the world's leading companies and institutes by developing practical fiber optic sensing solutions in many market areas including oil and gas, aerospace, renewable energy, marine, and civil engineering. As an ISO-9001 accredited company, Smart Fibres is highly committed to consistent quality manufacturing and efficient business operations. Our current developments are set to make fiber optic sensing more broadly available and economically viable as a performance optimization and asset management tool in a number of key volume sectors.

6 Phoenix Photonics Ltd.

Dean Giles dean.giles@phoenixphotonics.com www.phoenixphotonics.com

Phoenix Photonics designs and manufactures optical fiber components and equipment used in telecommunications, test and measurement equipment, fiber sensing, and research and development laboratories. Phoenix also works closely with the customer to provide customised solutions based on existing products and its core technology.

7 Nanoscribe GmbH

Sofía Rodríguez rodriguez@nanoscribe.de www.nanoscribe.de

Nanoscribe´s laser lithography systems “Photonic Professional” and “Photonic Professional GT” are designed for the fabrication of true three-dimensional micro- and nanostructures into photosensitive materials. The unique performance is based on two photon polymerization. Almost arbitrary complex shaped polymer structures with finest feature size in the sub-micrometer range were achieved. Speed, precision and extraordinary resolution are key features of Nanoscribe's table-top and fully automated 3D printers. The portfolio additionally comprises in-house developed resists tailored to the different needs of customers. The applications of the systems are widely spread, ranging from, e.g. Life Sciences, Cell Biology, Biomimetics, Photonics, Micro-Optics and Micro-Fluidics to Mechanical Metamaterials.

8 Ibsen Photonics A/S

Mr. Bjarke Rose Bjarke.Rose@ibsen.dk www.ibsenphotonics.com

Grating products for telecom include PING gratings for WSS/tunable filter/OCM applications and holographic Phase masks – additionally gratings for spectrometers and laser pulse compression/beam combining. For FBG sensing, Ibsen’s I-MON family of FBG Sensor System Interrogation Monitors offer very fast measurement frequency, high resolution, low power consumption and compact size.

9 Fibre Optic Security Systems

Vasily Yatseev yatseev@optolex.com www.optolex.com

Fiber Security ltd. (optolex™) provides the development and implementation of fiber optic intrusion detection system for extensive perimeters: large enterprises, airports, residential estates. The system is also suitable for distributed objects: oil and gas pipelines , water canals , railways. The company utilizes the highly sensitive hardware based on Rayleigh backscatter, which allows interrogating numerous kilometers of fibre cable, with the combination of latest pattern recognition algorithms, including neural networks. The principle is Rayleigh backscatter. The company teams with systems integrator, providing data for the upper-level system via Modbus over TCP IP.

10 Thorlabs GmbH

Julien Vigroux jvigroux@thorlabs.com www.thorlabs.de

Thorlabs, a vertically integrated photonics products manufacturer, was founded in 1989 to serve the laser and electro-optics research market. As new innovations came to market, Thorlabs extended its core competencies. The organization’s manufacturing capabilities include semiconductor fabrication of Fabry-Perot and DFB lasers, fiber draw towers, and advanced thin film deposition.

11 Ixfiber. Photline Technologies

Philippe LeRoux philippe.leroux@photline.com

www.photline.com

Photline Technologies is a leading supplier of optical modulation solutions. The company masters the entire chain of LiNb03 modulators production from computer-assisted design to final characterization, through wafer processing. iXFiber is an independent supplier of specialty optical fibers and optical components for telecommunication, defense, sensor and industrial markets. iXFiber is an independant supplier of specialty optical fibers and Bragg gratings for sensing, defense and industrial markets.

12 Fibersuntech S.L.

Tarek Murad talom@fibersuntech.com www.fibersuntech.com

Fibersuntech is a recently created Company dedicated to the distribution of optoelectronic devices targeting the general industry, telecom and renewable energy fields.

13 Exalos AG

Dr. Kevin Hsu hsu@exalos.com www.exalos.com

EXALOS is the world-leading company in superluminescent broadband light sources and high speed swept lasers, covering the visible and near-infrared wavelength range (400nm to 1700nm). These light sources are used in various fields spanning from navigation, optical coherence tomography, metrology, sensing, and microscopy.

14 Redondo Optics Inc.

Edgar Mendoza emendoza@redondooptics.com www.redondooptics.com

Redondo Optics, Inc. is a research and engineering company built on its own expertise in materials science, optics and fiber optics, electronics and signal processing. Its mission is to lead in the fiels of nanotechnology, advanced optical materials, optical sensors and instrumentation, and introduce disruptive products with applications in engergy, lightning and displays, life sciences and biotechnology, aerospace, telecommunications, and defense & security. Redondo Optics, Inc. offers a fiber optic oxygen sensor system with built-in optical temperature compensation. The FoxSense fiber optic oxygen sensor system uses Redondo Optics proprietary frequency domaine "phase-locked" detection technology.

15 Nufern

Kristoff Feliksik kfeliksik@nufern.eu www.nufern.com

Nufern is a leading U.S. manufacturer of specialty optical fibers, precision wound optical fiber coils, fiber lasers and amplifiers. Our integrated team has the experience, resources, and facilities required to design, manufacture, test and qualify highly-engineered optical fibers and fiber-based products for diverse applications and industries.

16 LQC S.L. – Ocean Optics

Marco Caceci info@lqc.es www.lqc.es

Headquartered in Dunedin, Fla., USA, Ocean Optics is a leading supplier of solutions for optical sensing - fundamental methods of measuring and interpreting the interaction of light with matter. Ocean Optics technologies include chemical sensors, analytical instrumentation, and optical fibers for use in diverse applications in medical and biological research, environmental monitoring, and science education. Ocean Optics product range includes UV, VIS, NIR, laser and LED light sources, UV, VIS, and NIR spectrometers, Raman and LIBS systems, fiber optics and probes both custom and off-the-shelf, integrating spheres, and an extensive range of accessories and standards. LQC is Ocean Optics distributor in Spain – call them for advise for any and all of your optical projects.

17 Bandweaver Technologies Co., Ltd. Gold Sponsor

Chao Lun Wu chaolun.wu@bandweaver.com www.bandweaver.co.uk

Bandweaver Technologies Co., Ltd. is a leading global supplier of optoelectronic components, fiber sensing equipment and security monitoring solutions. The company was established in Shanghai’s Zhangjiang High-Tech Park in 2002, with the investment over $30M. Our R&D Center and manufacturing are world class facilities. We have branches in Beijing, Guangzhou, Chengdu, Xi'an, Hong Kong, United Kingdom, and United States. Bandweaver is currently the only hi-tech optoelectronics company in China integrating the R&D and production of optical devices, application software, and complete customer solutions.

18 Fibotec Fiberoptics GmbH

Dr. Gerald Werner gerald.werner@fibotec.com

www.fibotec.com

Partners in Fiberoptics” Fibotec is a highly flexible market player in fiberoptics for communication, communication industry related test & measurement, and industrial applications. Typical products: Correlation-OTDR based Fault Locator, EDFA (also multi-stage pulsed MOPA systems), ASE-sources, customer specific sensors and fiber coupled light sources for printing applications

19 Inphenix, Inc.

Wei-Wei Zhang wzhang@inphenix.com

www.inphenix.com

InPhenix, a privately held company headquartered in Livermore CA, designs and manufactures active optoelectronic components and modules. Our facility includes a state-of-the-art wafer fab, a production area with complete packaging capabilities, and chip-level to module-level testing. Products include Semiconductor Optical Amplifiers(SOA), Superluminescent Diodes(SLD), Gain Chips, DFB Lasers & Fabry-Perot Lasers.

20 BaySpec, INC. Gold Sponsor

www.bayspec.com

BaySpec, Inc. is a vertically integrated spectral sensing company. The company designs, manufactures and markets advanced spectral instruments, from UV-VIS spectrometers to handheld and portable NIR and Raman analyzers, for the biomedical, pharmaceuticals, chemical, food, semiconductor, homeland security, and the optical telecommunications industries.

21 NBG Systems GMBH Gold Sponsor

Karl Bauer – CEO office@nbg.co.at

www.nbg-systems.com

NBG Systems GmbH is the face to the customer, to trade and coordinate all NBG Holding GmbH companies products. FCT Fiber Cable Technology GmbH, a subsidiary company of NBG Holding GmbH, develops and manufactures Special Fiber In Metal Tubes (FIMT) for Fiber Optic Sensing Applications (FOSA) and the telecommunication industry. NBG Holding GmbH is shareholder of the Safibra s.r.o. corporation. Safibra builds measurement, diagnose and analysing tools for fiber optic sensing applications. NBG FOSA s.r.o, provides turnkey solutions in the field of fiber optic sensing applications, such as structural health monitoring, distributed temperature and strain sensing or weigh in motion concepts. Infra Sensor Solutions focuses on supplying measurement data, obtained through monitoring infrastructural installations (civil engineering structures, roads, railways, dykes, Weigh-In-Motion, etc.) using state-of-the-art fiber optic (measurement) technology. NBG Systems offers with it’s companies a rich knowledge base in fiber optic sensing applications. Customers will profit from NBG’s integrated fiber optics experience and turnkey solutions.

22 Fiberguide Industries, Inc. Gold Sponsor

Rosina Gocek rgocek@fiberguide.com www.fiberguide.com

For more than three decades Fiberguide Industries has been a reliable, long-term, strategic partner with OEM manufacturers in providing efficient, cost-effective, practical fiber optic solutions engineered to meet their specific needs. We specialize in manufacturing large core specialty optical fiber, high temperature metalized optical fibers, and we package these fibers in a variety of assemblies / bundles used for optical power delivery and optical sensing applications. With Corporate headquarters and fiber manufacturing located in Stirling, New Jersey; applications engineering, component, and assembly manufacturing in Caldwell, Idaho; as well as a sales office and manufacturing in Shanghai, China; Fiberguide Industries is well positioned to serve the needs of our global customers.

23 Luna Silver Sponsor

Ian Shannan shannani@lunainc.com

www.lunainc.com

We are scientists, engineers, and business professionals; driving breakthroughs in fields as diverse as aerospace, automotive, energy, defense, healthcare, and telecommunications. We research, develop and commercialize innovative technologies: Strain & temperature sensing, Test and measurement, Shape sensing.

24 NKT Photonics Gold Sponsor

Søren Løvgreen sl@nktphotonics.com

www.nktphotonics.com

NKT Photonics produce Koheras single frequency low noise fiber lasers, SuperK supercontinuum whitelight sources, photonic crystal fibers and high power picosecond lasers. The Koheras lasers are a special range of ultra stable, low noise DFB (Distributed Feedback) fiber lasers with unique characteristics for coherent acoustic detection in oil & gas exploration, pipeline monitoring, perimeter security, vibrometry and wind Lidar, as well as in more scientific oriented applications within metrology and atomic physics. The Koheras lasers are inherent single frequency CW sources with extremely low phase noise and narrow linewidth down to the Hz range. The low noise makes these lasers ideal for coherent sensor interferometry where external acoustic perturbations can be sensed with high sensitivity and over large (tens of km) ranges in optical fibers. The lasers are configurable from low power single line lasers, to multi-wavelength and high power systems.

25 Optiwave Systems Inc.

Bryan Tipper info@optiwave.com

www.optiwave.com

Optiwave Systems is an R&D company specializing in the development and commercialization of scientific and engineering software for numerical simulation of integrated and fiber optic devices and systems. For more information on our products or services please visit us online @ optiwave.com.

26 Hamamtsu Photonics France

Víctor Bernardo Puente vbernardo@hamamatsu.es

www.hamamatsu.es

Hamamatsu Photonics is a world-leading manufacturer of opto-electronic components and systems and employs over 4000 staff worldwide. The corporate headquarters are based in Hamamatsu City, Japan along with six manufacturing plants and central research laboratories. Since its inception in 1953, Hamamatsu Photonics has expanded to now enjoy a global presence with production facilities, business locations and associated companies throughout Asia, Europe and North America. Hamamatsu Photonics’ corporate philosophy stresses the advancement of Photonics through extensive research and development. Hundreds of new opto-electronic products are introduced to the market each year and many Hamamatsu products are regarded as state-of-the-art. Hamamatsu sources, detectors and imaging products are designed to cover the entire optical spectrum, from nuclear radiation, x-ray, Ultraviolet (UV), Visible and Infrared radiation. Hamamatsu devices provide solutions for a wide variety of applications including analytical, industrial and medical instrumentation. Photonics has vast potential for applications in basic research in fields such as physics, chemistry and biology. It is expected to further contribute to innovation in many medical and industrial applications such as high-speed telecommunication and information processing, DNA / proteomics / genomics research, biotechnology, security, pollution monitoring, spectroscopy and many other applications.

27 Vytran Llc.

Pascal Voluer pvoluer@vytran.com

www.vytran.com

Vytran produces in-plant equipment for optical fiber stripping, cleaning, cleaving, splicing, recoating and testing. Our newest splicer, “CAS-4100,” is a high-performance, compact, automated tool ideal for fiber assembly production. Our all-in-one “FAS”workstation is designed for high-volume, low-cost fiber assembly manufacturing, including EDFA, DCF and others.

28 Perfos

David Méchin dmechin@perfos.com

www.perfos.com

PERFOS develops Custom Microstructured Fibers from conception to integration: Different material (silica or chalcogenide); preform, capillaries, tapers, fiber components for all applications: scientific, defense, biophotonics, energy, telecom, etc. PERFOS carries out studies for innovative small and medium size businesses, willing to develop new systems based on photonics : • Comparative studies • Bibliographic research • From global technical studies to specific study for re-engineering PERFOS also responds to public agencies requesting expertise, impact or development studies on photonics for other economic sectors (agriculture, defense, etc.)

29 IDIL Fibres Optiques

David ASSOUS david.assous@idil.fr

www.idil.fr

IDIL is specialized in the design, development, manufacturing and distribution of fibered systems intended for science, defence and industry markets, i-e fiber optics as well as passive and active optical components, electronics and software control. IDIL provides some specific studies covering prototype creations but also little and medium mass production.

30 Alava Ingenieros S.A.

Sergio Arroniz sarroniz@alava-ing.es www.alavaingenieros.com

Alava Ingenieros Group is an entirely privately owned group which has been providing high technology solutions in the Testing, Measurement, Communications, Security, Defence and Preventive Maintenance fields since it was first founded in 1973.The group offers consultancy, engineering, distribution, training and technical services, providing turn-key projects for several sectors including Aerospace, Automotive, Security, Defence, Energy, Communications and Finance, as well as Testing and Research Centres, Universities, Public Services and Industry in general.

31 Santec Corporation

Ben Lee benlee@santec.com www.santec.com

With 30 years of experience in the optics industry Santec has command of the key manufacturing processes to build lasers, instruments and components that meet the stringent demands for excellence by our customers. By committing to innovation as well as listening to our customer requests, Santec has succeeded in introducing solutions for a broad range of new optical applications. Our drive for Optopia has resulted in steps that minimize the timeline for a product to go from conception to commercial applications.

32 Gaussian Optics Co, Ltd.

Nick nick@gaussianoptics.com www.gaussianoptics.com

GAUSSIAN OPTICS CO., LTD is launched in 2008 and located in Optical Valley, China. It is one of the main optical sensor module providers in China. FBG spectrum analysis modules and xOTDR modules are the major products of Gaussian Optics. Reliable and stable product quality is always the first priority. Gaussian Optics has established the whole quality control system to guarantee the product performance and the reliability, stability and EMC of the products are considerately assessed and qualified. Gaussian Optics’ modules can be conveniently integrated into optical sensing system without other complicated optical assembling works which has the significant benefit to reduce the development period and total cost. Gaussian Optics is always your trustworthy co-operation friend.

33 InPhoTech Ltd Gold Sponsor

Piotr Nasilowski inphotech@inphotech.pl www.inphotech.eu

InPhoTech elaborates advanced solutions based on photonics in response to the current demands of industry. InPhoTech carries out research, development and fabrication of innovative photonic systems and components, which serve a diverse range of research and industrial applications, including sensing, monitoring, medicine, defense, telecom and light sources. The main technology employed by InPhoTech to manage light is the specialty optical fiber technology including microstructured fibres. This technology largely benefited from the evolution of telecommunication in the late 90's. However fibers developed for telecommunication applications can be used in a very limited number of other applications. Therefore, solutions offered by InPhoTech rely on the specialty fibers with precisely tailored properties. Each of our products is dedicated and optimized for the specific application, which makes our products very unique worldwide. Our core product, optical fiber sensors, is advantageous over standard fibre sensors due to a number of advantages: • all advantages of standard fibre sensors, • extreme sensitivities, • minimizing cross-sensitivities, • operating in extreme temperatures.

Technical Co-Sponsors

Institutional Sponsors

Sponsors

Platinum Sponsor

Gold Sponsors

Silver Sponsor

Bronze Sponsors

Awards Sponsors