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March / 2012 Remote Sensing • Photovoltaics Produciton • Prism Award Winners Photonics Innovation Celebrated page 71 Multispectral Imaging Explores Harsh Environments
March / 2012
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PhotonicsInnovationCelebratedpage 71
Multispectral ImagingExplores HarshEnvironments
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March 2012
t TABLE OF CONTENTS
16 | TECH NEWSPhotonics Spectra editors curate the most significant photonics research and technology headlines of the month – and take you deeper inside the news. Featured stories include:
• TIGO laser ranging telescope targets satellites• Masking moments in time by splitting light• 2-million-degree matter reveals the structure of stars
36 | FASTTRACKBusiness and Markets
The impact of Thailand’s epic flood continues into 2012Optics industry on steady ground after quakeKodak to delete its digital device division
45 | GREENLIGHTSolar concentration without mirrors
10 | EDITORIAL
47 | LASERS IN USELessons learned from a recent laser accidentby Michael B. Woods, SLAC National Accelerator Laboratory
90 | PEREGRINATIONSOut of the blue, into the office
NEWS & ANALYSIS
76 | BRIGHT IDEAS87 | HAPPENINGS89 | ADVERTISER INDEX
DEPARTMENTS
COLUMNS
THE COVERThe many ways remote sensors are used to explore the most forbidding areas on theplanet inspired this month’s cover art. Articleby Lynn Savage on page 50. Design by SeniorArt Director Lisa N. Comstock.
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Photonics Spectra March 20124
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PHOTONICS: The technology of generating and harnessing light and other forms of radiantenergy whose quantum unit is the photon. The range of applications of photonics extendsfrom energy generation to detection to communications and information processing.
Volume 46 Issue 3
www.photonics.com
50 | MULTISPECTRAL IMAGING EXPLORES HARSH ENVIRONMENTS by Lynn Savage, Features EditorBy gathering data on environments that are dangerous for humans, remote sensing helps determine the health of the ecosystem.
58 | ULTRAFAST FIBER LASERS ENABLE UNIQUE MATERIALS RESEARCHby Dr. Tony Lin, Calmar Laser Inc.The robust architecture and and low maintenance of fiber-based architectures, along with extraordinary performance parameters, are enabling innovative laboratory research.
61 | LASERS CHANGE THE SHAPE OF THE PHOTOVOLTAICS INDUSTRYby Marie Freebody, Contributing EditorPV development and manufacturing are well served by laser technology, includingprocesses such as doping, welding, ablation, trenching and drilling.
64 | NEXT-GENERATION CMOS REDEFINES TRADE-OFFS FOR INSPECTIONby Behnam Rashidian and Eric Fox, Teledyne DalsaTo arrive at the best CMOS imaging device design, both the physics of operating the device and the practicalities of implementing the design must be considered.
67 | PHOTONIC SENSORS HELP KEEP EARTH CLEAN, GREENby Dr. Radu Barsan, Rio Inc.In energy sectors ranging from fossil fuel to geothermal, photonic technologies are playing various roles in developing and maintaining clean, efficient systems.
71 | 2011 PRISM AWARDS WINNERSby Melinda Rose, Senior EditorA wrap-up of this year’s winning entries highlights the amazing innovations of the photonics industry.
PHOTONICS SPECTRA ISSN-0731-1230, (USPS 448870) ISPUBLISHED MONTHLY BY Laurin Publishing Co. Inc., BerkshireCommon, PO Box 4949, Pittsfield, MA 01202, +1 (413) 499-0514; fax: +1 (413) 442-3180; e-mail: [email protected]. TITLE reg. in US Library of Congress. Copyright ® 2012by Laurin Publishing Co. Inc. All rights reserved. Copies of Pho-tonics Spectra on microfilm are available from University Mi-crofilm, 300 North Zeeb Road, Ann Arbor, MI 48103. PhotonicsSpectra articles are indexed in the Engineering Index. POST-MASTER: Send form 3579 to Photonics Spectra, Berkshire Com-mon, PO Box 4949, Pittsfield, MA 01202. Periodicals postagepaid at Pittsfield, MA, and at additional mailing offices. CIRCU-LATION POLICY: Photonics Spectra is distributed withoutcharge to qualified scientists, engineers, technicians, and man-agement personnel. Eligibility requests must be returned withyour business card or organization’s letterhead. Rates for oth-ers as follows: $122 per year, prepaid. Overseas postage: $28surface mail, $108 airmail per year. Inquire for multiyear sub-scription rates. Publisher reserves the right to refuse nonquali-fied subscriptions. ARTICLES FOR PUBLICATION: Scientists,engineers, educators, technical executives and technical writersare invited to contribute articles on the optical, laser, fiber optic,electro-optical, imaging, optoelectronics and related fields.Communications regarding the editorial content of PhotonicsSpectra should be addressed to the managing editor. Con-tributed statements and opinions expressed in Photonics Spec-tra are t hose of the contributors – the publisher assumes noresponsibility for them.
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FEATURES
Photonics Spectra March 2012 5
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Photonics Spectra March 2012
Group Publisher Karen A. Newman
Editorial Staff
Managing Editor Laura S. MarshallSenior Editor Melinda A. Rose
Features Editor Lynn M. SavageEditors Caren B. Les
Ashley N. PaddockCopy Editors Judith E. Storie
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e EDITORIAL COMMENT
Make Nothing Happen
Before I get out of bed in the morning, before I can even read the numbers on theclock, I have to put on my glasses. I wear contacts during the day, and if I want toclearly see words on my computer screen, I have to put on my reading glasses, too.
But I consider myself lucky that my vision can still be corrected.
Working in a laser lab – or any environment where lasers are in use – without wearingprotective eyewear puts you at risk for eye injuries that can damage your vision beyondthe help of any glasses or contacts. Imagine getting up in the morning and not being ableto see the clock at all, the smile of your spouse or the first robin of spring. Specific dataabout workplace laser injuries to the eye is not easy to find, but even one such accident isone too many.
Eye injuries may be just the tip of the iceberg where laser accidents are concerned, butthey are easily preventable. Still, we receive photos of students and researchers who arenot wearing laser safety eyewear, standing close to working lasers and putting themselvesat risk. Not only should these photos not be sent out with press releases, they should noteven be taken. Even photos staged for the camera should observe appropriate laser safety.It’s about setting an example for students and others new to lasers.
Despite our vigilance, such photos occasionally do get printed in Photonics Spectra.Please don’t think that means we condone the unsafe use of lasers. In fact, to underscoreour concerns about laser safety, in this issue we are launching “Lasers in Use,” a columnwritten by people working at the front lines of laser safety.
In “Lessons Learned from a Recent Laser Accident,” Michael Woods, the laser safety officer at SLAC National Accelerator Laboratory, recounts an incident in which a graduatestudent was injured while adjusting a polarizing beamsplitter being used with a femtosec-ond Ti:sapphire laser. His account carries valuable information about the root causes of the accident and the corrective actions taken. Read the column beginning on page 47.
Peter Baker, the executive director of LIA (Laser Institute of America), the professionalorganization for laser applications and safety, wrote a column called “When Nothing Happens” last year for his organization’s newsletter. In it, he wrote:
“When nothing happens in a laser environment, does it mean that nothing was done? Notat all! If there is no loss of sight, no burned skin, no inhalation of noxious fumes and noelectric shock, then it means that a lot has been done.
“It means that the organization with the laser has taken the responsible approach to usingit, has appointed a trained or certified laser safety officer, complied with the guidelines set out in the ANSI Z136 series of standards and provided a safe environment with appro-priate training for its people. Our laser safety officers do a great job keeping people safeand ensuring that nothing happens. This is an important and underappreciated factor in the rapidly increasing growth of the laser industry.”
LIA has served the industrial, medical, research and government communities for morethan 40 years with technical information, training and networking opportunities for laserusers from around the globe. Visit it at www.lia.org.
So, what are you doing to make nothing happen in your laser lab? Send us a photo of youand your colleagues exhibiting proper regard for laser safety. We’ll feature the best ofthem in August as part of Photonics Spectra’s annual list issue.
Editorial Advisory Board
Dr. Robert R. AlfanoCity College of New York
Valerie C. BolhouseConsultant
Walter BurgessPower Technology Inc.
Dr. Timothy DayDaylight Solutions
Dr. Anthony J. DeMariaCoherent-DEOS LLC
Dr. Donal DenvirAndor Technology PLC
Patrick L. EdsellAvanex Corp.
Dr. Stephen D. FantoneOptikos Corp.
Randy HeylerOndax Inc.
Dr. Michael HoukBristol Instruments Inc.
Dr. Kenneth J. KaufmannHamamatsu Corp.
Brian LulaPI (Physik Instrumente) LP
Eliezer ManorShirat Enterprises Ltd., Israel
Shinji NiikuraCoherent Japan Inc.
Dr. Morio Onoeprofessor emeritus, University of Tokyo
Dr. William PlummerWTP Optics
Dr. Richard C. PowellUniversity of Arizona
Dr. Ryszard S. RomaniukWarsaw University of Technology, Poland
Samuel P. SadouletEdmund Optics
Dr. Steve ShengTelesis Technologies Inc.
William H. ShinerIPG Photonics Corp.
John M. StackZygo Corp.
Dr. Albert J.P. TheuwissenHarvest Imaging/Delft University
of Technology, Belgium
Kyle VoosenNational Instruments Corp.
10 Photonics Spectra March 2012
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Welcome to
Photonics Spectra March 201212
Photonics Media’s industry-leading site features the latest industry news and events from around the world.
Research news: A roundup of the industry’s top research headlines.Light Matters weekly newscast: A video recap of the most compelling optics and photonics news brought to you by editors from Photonics.com, and Photonics Spectraand BioPhotonics magazines. Business news: We keep you up-to-date with the latest mergers, acquisitions, financial reports, grants, patents and more.Popular Topics: Check out the most-viewed stories from Photonics.com.Fiber Market Report: A direct link to information about the seven-year forecast for the fiber optics components market, brought to you by 30-year industry veteran David Chaffee in collaboration with Laurin Publishing. Light Exchange: An easy link to all of our social media sites, including Facebook, Twitter, blogs, forum and our poll question section.
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Check out a sample of the new digitalversion of Photonics Spectra magazine at www.photonics.com/DigitalSample. It’s a whole new world of information forpeople in the global photonics industry.
In the April issue of
Photonics Spectra …Precision Noncontact Metrology Application Factors
Competing requirements for the most challenging measurement applications in industry and other technical endeavors can be daunting when their complexitytakes the design or application engineer into territory that is "uncharted" in his orher particular experience. Coherix Inc. looks at how to evaluate a measurementapplication's requirements.
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TIGO laser ranging telescope targets satellitesDARMSTADT, Germany – It was like aplanetary-scale video game: Working fromorbital predictions, a research team tookthe first laser measurements of Galileo operational satellites in orbit using lasersin Chile.
The Transportable Integrated GeodeticObservatory (TIGO) performed the laserranging at an altitude of 23,230 km usinga near-infrared laser beam. The TIGOteam members, led by Michael Häfner andMarcos Avendaño, took aim with their
laser and fired, having first calibrated itusing Europe’s first test navigation satel-lite, GIOVE-A. The orbital predictionshad been provided by the ESA’s EuropeanSpace Operations Center.
TIGO is equipped for various observa-tions – in 2006, its radio telescope moni-tored ESA’s first moon mission, SMART-1, to determine end-of-mission impact onthe lunar surface.
The Galileo satellites – as with manymodern satellites – are fitted with reflec-
tors that bounce the laser pulse back to itsoriginal location. The time the laser takesto return to the ground is measured withan ultraprecise timer. The speed of light isfixed, so the distance to the satellite can be measured with an accuracy of betterthan 1 cm.
TIGO is owned by the Federal Agencyfor Cartography and Geodesy and hasbeen operating jointly with the Universityof Concepción and the Chilean MilitaryGeographical Institute since 2002. It wasestablished to fill gaps in various types of worldwide geodetic measurements.
TIGO was the first station in the 40-strong International Laser Ranging Servicenetwork to range the Galileo satellites,with Herstmonceux in the UK and Materain Italy among the next Satellite LaserRanging stations to succeed.
Besides being widely used for preciseorbit determination of satellites, laserranging also is employed for calibratingsatellite instruments, contributing to theInternational Terrestrial Reference Frame(Earth’s standardized geodetic coordinatesystem) and measuring slight ground mo-tion resulting from tectonic plate dynam-ics. It also can measure the moon’s dis-tance from Earth, thanks to laser reflectorsleft on the lunar surface by the US and Soviet Union.
NEWSTECH
Photonics Spectra March 201216
A closer look at the most significant photonics research and technology headlines of the month
Satellite Laser Ranging telescope at the TIGO ground station. The laser operates at a near-infrared wavelength of 847 nm.
TIGO performed the world’s first laser ranging of the first Galileo satellite on Nov. 27, 2011. TIGO was put in place to fill gaps in various types of worldwide geodetic measurements. Courtesy of ESA/TIGO – BKG/UdeC/IGM.
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17Photonics Spectra March 2012
ITHACA, N.Y. – A techniquethat employs a split-time lens tobreak light into its slower (red)and faster (blue) componentscreates a temporal gap, albeit atthe picosecond timescale, engi-neers at Cornell Universityhave reported.
The optical fiber-based sys-tem steers light “around” anevent so that no evidence, suchas a change in the temporal orspectral properties of the lightbeam, is detectable.
Applied engineering andphysics professor AlexanderGaeta and colleagues were in-spired by a theoretical proposalout of Imperial College Londonin 2010 for a space-time cloakor “history editor” that sug-gested that a gap could be created by accelerating and decelerating parts of light by
changing the composition of thefiber at a rate fast enough tochange light’s velocity – noeasy task.
“Instead, we thought ratherthan changing the property ofthe material, we could changethe property of the light. This ismuch easier and has the sameeffect as changing the composi-tion,” team member and post-doc Moti Fridman told TheCornell Daily Sun.
The property of the lighttraveling through the fiber waschanged by using time lensesthat change light’s speed via afour-wave mixing technique.
They were able to mask anevent – in this case a ball tryingto pass through a green beam oflaser light without detection –for 50 ps, or 50-trillionths of a second.
The gap created might be increased up to 10 ns, Gaetasaid, and the technique couldhave applications in fiber opticdata transmission, such as in-serting an emergency messagewithout interrupting or disturb-ing the data stream, and in dataprocessing, such as multitask-ing operations in light-basedcomputers.
The scientists now are work-ing to extend the amount oftime that they can achieve withthe cloak and are also workingtoward what they believe couldbe another practical application.
There are a lot of differentways to manipulate light, Gaetasaid, “and this experiment ofcloaking is a demonstration ofthe very unusual ways in whichwe can control light and reallycontrol its properties.”
Fridman hopes the work will inspire more people to getinvolved in science, he told the Sun.
“Maybe more kids will bedrawn to science because ofthis experiment,” he said. “If this is the case, then I havedone my job.”
“It’s nice to achieve some-thing once in a while that ap-peals to the nonscience commu-nity as well,” Gaeta added.“Every scientist should experi-ence the feeling at least once in their lifetime.”
The research, funded byDARPA and the Cornell Centerfor Nanoscale Systems, ap-peared in the Jan. 5 issue ofNature (doi: 10.1038/nature10695).
Masking moments in time by splitting light
2-million-degree matter reveals the structure of starsMENLO PARK, Calif. – Using the world’smost powerful x-ray laser, scientists havecreated and probed a 2-million-degreepiece of “hot, dense matter” in a controlledway for the first time. This is a significantstep forward in understanding the most ex-treme matter found at the center of giantplanets and stars, and it could help experi-ments aimed at recreating the nuclear fusion process that powers the sun.
Researchers at the SLAC National Accelerator Laboratory conducted experi-ments using its Linac Coherent LightSource (LCLS), which produces laserpulses 1 billion times brighter than thoseof any earlier x-ray source. They used itspulses to flash-heat a small piece of alu-minum foil, generating solid plasma witha temperature of about 2 million degrees.The whole process took less than one-tril-lionth of a second.
“Making extremely hot, dense matter is important scientifically if we are ulti-mately to understand the conditions that
exist inside stars and at the center of giantplanets within our own solar system andbeyond,” said Sam Vinko, a postdoctoralresearcher at Oxford University and lead
author of the paper, which appeared inNature (doi: 10.1038/nature10746).
Scientists have long been able to createplasma from gases and study it with con-
The interior of a Linac Coherent Light Source SXR experimental chamber, set up for an investigation to createand measure a form of 2-million-degree matter. The central part of the frame contains the holder for the material that will be converted into hot, dense matter. To the left is an extreme-UV spectrometer, and to theright is a small red laser set up for alignment and positioning. Courtesy of University of Oxford/Sam Vinko.
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t TECHNEWS
Photonics Spectra March 2012
ventional lasers, said co-author Bob Na-gler of SLAC, an LCLS instrument scien-tist. But no tools were available for doingthe same at solid densities that cannot bepenetrated by conventional laser beams.
Now, with its ultrashort wavelengths of x-ray laser light, the LCLS can pene-trate a dense solid to create a uniformpatch of plasma – in this case, a cube one-thousandth of a centimeter on a side – andprobe it at the same time, Nagler said.
The resulting measurements, he said,will feed back into theories and computer
simulations of how hot, dense matter be-haves. This could help scientists analyzeand recreate the nuclear fusion processthat powers the sun.
The Oxford-led research team includedscientists from SLAC (a multiprogramlaboratory operated by Stanford Universityfor the US Dept. of Energy’s Office ofScience) and from Lawrence Berkeley andLawrence Livermore national laboratories,as well as from five other international institutions.
Amorphous silicon makes better optical fibersCOLLEGE PARK, Pa. – A first-of-its-kindtechnique deposits a noncrystalline formof silicon into the long, ultrathin pores ofoptical fibers, making more flexible andefficient fibers. This method uses high-pressure chemistry to make well-devel-oped films and wires from this particularkind of silicon semiconductor.
Hydrogenated amorphous silicon isideal for solar cell applications and couldalso be useful for the light-guiding coresof optical fibers, said John Badding, achemistry professor at Pennsylvania State
University. He added, however, that de-positing the silicon compound into a tinyoptical fiber presents a challenge.
“Traditionally, hydrogenated amorphoussilicon is created using an expensive labo-ratory device known as a plasma reactor,”Badding said. “Such a reactor begins witha precursor called silane – a silicon-hydro-gen compound. Our goal was not only tofind a simpler way to create hydrogenatedamorphous silicon using silane, but also touse it in the development of an opticalfiber.”
A bed of amorphous hydrogenated silicon wires that were prepared in the pores of optical fibers. The wireshave been chemically etched out of the optical fiber to reveal them. Scale bar = 100 µm. Inset: An array ofamorphous hydrogenated silicon tubes deposited in an optical fiber. The optical fiber has been cleaved in halfto reveal the array of tubes. The very thin glass walls of the fiber surrounding each tube are largely obscured.Courtesy of John Badding Lab, Pennsylvania State University.
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The low-pressure plasma reactor tech-nique works well for depositing hydro-genated amorphous silicon onto a surfaceto make solar cells. However, the methodcannot be used for depositing hydrogen-ated amorphous silicon into fiber – so theteam had to rethink the approach.
“The trick was to develop a high-pres-sure technique that could force the mole-cules of silane all the way down into thefiber and then also convert them to amor-phous hydrogenated silicon,” said Pier J.A.Sazio of the University of Southampton inthe UK, a team leader. “The high-pressure
chemistry technique is unique in allowingthe silane to decompose into the useful hy-drogenated form of amorphous silicon,rather than the much less useful nonhydro-genated form that otherwise would formwithout a plasma reactor. Using pressure in this way is very practical because theoptical fibers are so small.”
Optical fibers with a noncrystallineform of silicon have many applications,such as in telecommunication devices orfor changing laser light into different in-frared wavelengths. IR light could be usedto improve surgical techniques, military
countermeasure devices and chemical-sensing tools, such as those that detectpollutants or environmental toxins. Theteam members also hope that their re-search will be used to improve existingsolar cell technology.
“What’s most exciting about our re-search is that, for the first time, opticalfibers with hydrogenated amorphous sili-con are possible,” Badding said. “How-ever, our technique also reduces certainproduction costs, so there’s no reason itcould not help in the manufacturing of less expensive solar cells as well.”
One-step process turns carbon fibers into graphene QDsHOUSTON – Common carbon fiber canbe turned into graphene quantum dots(QDs) in a one-step chemical process thatis much simpler than established tech-niques. This discovery could prove use-ful for optical, biomedical and electronicapplications.
“There have been several attempts to
make graphene-based quantum dots withspecific electronic and luminescent prop-erties using chemical breakdown or e-beam lithography of graphene layers,”said Pulickel Ajayan, a materials scientistat Rice University. “We thought that asthese nanodomains of graphitized carbonsalready exist in carbon fibers, which are
cheap and plenty, why not use them as the precursor?”
Ajayan’s lab collaborated with col-leagues in China, India, Japan and theTexas Medical Center to discover theprocess.
Quantum dots, discovered in the 1980s,are semiconductors that contain a size-
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and shape-dependent bandgap. These havebeen promising structures for applicationsthat range from computers, LEDs, solarcells and lasers to medical imaging devices. The sub-5-nm carbon-based QDs produced in bulk through the newwet chemical process are highly soluble,and their size can be controlled via thetemperature at which they’re created.
The researchers were attempting an-other experiment when they came acrossthe technique. “We tried to selectively oxi-dize carbon fiber, and we found that wasreally hard,” said Wei Gao, a graduate stu-dent. “We ended up with a solution and
decided to look at a few drops with a transmission electron microscope.”
The specks they saw were oxidized nano-domains of graphene extracted via chemi-cal treatment of carbon fiber. “That was a complete surprise,” Gao said. “We call
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This transmission electron microscope image showsa graphene quantum dot with zigzag edges. TheQDs can be created in bulk from carbon fiberthrough a chemical process discovered at Rice University. Courtesy of Ajayan Lab/Rice University.
Green-fluorescing graphene quantum dots createdat Rice University surround a blue-stained nucleus in a human breast cancer cell. Cells were placed in a solution with the QDs for four hours. The QDs,each smaller than 5 nm, easily passed through thecell membranes, showing their potential value forbioimaging.
Dark spots on a transmission electron microscopegrid are graphene quantum dots made through awet chemical process at Rice University. The inset is a close-up of one QD. Graphene QDs may find use in electronics, optical and biomedical applications.
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them quantum dots, but they’re two-dimensional, so what we really have here are graphene quantum discs.”
Gao said that other techniques are ex-pensive, and they take weeks to makesmall batches of graphene quantum dots.“Our starting material is cheap, commer-cially available carbon fiber. In a one-steptreatment, we get a large amount of quan-tum dots. I think that’s the biggest advan-tage of our work,” she said.
Further experimentation revealed thatthe size of the QDs, and their photolumi-nescent properties, could be controlledthrough processing at relatively low tem-peratures, from 80 to 120 °C. “At 120, 100 and 80 degrees, we got blue, greenand yellow luminescing [quantum] dots,”she said.
They also found that the QDs’ edgestended to prefer the form known as zig-zag. The edge of a sheet of graphene – the single-atom-thick form of carbon – determines its electrical characteristics,and zigzags are semiconducting.
Luminescent properties give graphenequantum dots the potential for imaging, pro-tein analysis, cell tracking and other bio-medical applications, Gao said. Tests atHouston’s MD Anderson Cancer Center andBaylor College of Medicine on two human
breast cancer lines showed that the QDseasily found their way into the cells’ cyto-plasm and did not interfere with their prolif-eration.
“The green quantum dots yielded a verygood image,” said Rebeca Romero Aburto,a graduate student in the Ajayan Lab whoalso studies at MD Anderson. “The advan-tage of graphene [quantum] dots overfluorophores is that their fluorescence ismore stable and they don’t photobleach.They don’t lose their fluorescence as eas-ily. They have a depth limit, so they maybe good for in vitro and in vivo studies,but perhaps not optimal for deep tissues in humans.”
The quantum dots could be an interest-ing approach for further exploration ofbioimaging, she said. “In the future, thesegraphene QDs could have high impact be-cause they can be conjugated with otherentities for sensing applications too.”
The results were published online inNano Letters (doi: 10.1021/nl2038979).The research was supported by Nanohold-ings, the Office of Naval Research MURIprogram on graphene, the Natural ScienceFoundation of China, the National BasicResearch Program of China, the Indo-USScience and Technology Forum, and theWelch Foundation.
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Photonics Spectra March 2012
Streak camera stops light for trillion-fps videoCAMBRIDGE, Mass. – A novel streakcamera that captures images in picosecondincrements now makes it possible to stopnot just a bullet piercing an apple or ahorse in mid-canter, but light particlesthemselves as they traverse ascene.
The camera, created in MIT’sMedia Lab, can acquire data at a rate of 1 trillion exposures persecond. That hyperfast rate pro-duces a slow-motion video of aburst of light traveling thelength of a 1-liter soda bottle,bouncing off the cap and reflect-ing back toward the bottle’s bot-tom. The work follows in thefootsteps of Stanford Univer-sity’s Eadweard Muybridge,whose 19th-century photo-graphic technique first showedthe stages of a horse’s gallop,and of MIT’s own Harold Eu-gene “Doc” Edgerton, whose120 strobe flashes per second
helped capture the iconic image of a pro-jectile puncturing a whole apple.
This is the ultimate in slow motion, saidMedia Lab postdoc Andreas Velten, one ofthe system’s developers. “There’s nothing
An ultrafast imaging system developed at MIT differs from otherhigh-speed imaging systems in that it can capture light scatteringbelow the surfaces of solid objects, such as the tomato depictedhere. Courtesy of Di Wu and Andreas Velten, MIT Media Lab.
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in the universe that looks fast to this camera,” he said.The system relies on streak camera technology, although it is
deployed in an unexpected way. The aperture of the streak cam-era is a narrow slit. Photons enter the camera through the slit andpass through an electric field that deflects them in a direction per-pendicular to the slit. Because the electric field is changing veryrapidly, it deflects late-arriving photons more than it does early-arriving ones.
The image produced by the camera is therefore two-dimen-sional; however, only one dimension – the one corresponding tothe direction of the slit – is spatial. The other dimension, corre-sponding to the degree of deflection, is time. The image thus represents the time of arrival of photons passing through a one-dimensional slice of space.
The camera was intended for use in experiments where lightpasses through, or is emitted by, a chemical sample. Becausechemists are interested chiefly in the wavelengths of light that asample absorbs, or in how the intensity of the emitted lightchanges over time, the fact that the camera registers only one spatial dimension is irrelevant.
But that’s a serious drawback in a video camera. To producetheir super-slow-motion videos, Velten and his colleagues –Media Lab associate professor Ramesh Raskar and professor ofchemistry Moungi Bawendi – must perform the same experimentrepeatedly, continually repositioning the streak camera to gradu-ally build up a two-dimensional image. It takes only a nanosec-ond for light to traverse the bottle, for example, but it takes aboutan hour to collect all the data necessary for the final video. Forthat reason, Raskar calls the new system “the world’s slowestfastest camera.”
After an hour, the researchers accumulate hundreds of thou-sands of data sets, each of which plots the one-dimensional posi-tions of photons against their times of arrival. Raskar, Velten andother members of Raskar’s Camera Culture group at the MediaLab developed algorithms that can stitch that raw data into a setof sequential two-dimensional images.
Because the ultrafast imaging system requires multiple passesto produce its videos, it can’t record events that aren’t preciselyrepeatable. Any practical applications will probably involve caseswhere the way in which light scatters is itself a source of usefulinformation. Those cases may, however, include analyses of the
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Photonics Spectra March 2012
Media Lab postdoc Andreas Velten, left, and associate professor Ramesh Raskarwith the experimental setup they used to produce slow-motion video of light scattering through a plastic bottle. Courtesy of M. Scott Brauer.
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physical structures of manufactured mate-rials and biological tissues – “like ultra-sound with light,” Raskar said.
If the event is not repeatable, the groupreported, the required signal-to-noise ratiowould make it nearly impossible to cap-ture the event. Instead, the researchers ex-ploit the fact that the photons statisticallywill trace the same path in repeated pulsedilluminations. Careful synchronization ofthe pulsed light with the capture of re-flected light allows them to record thesame pixel at the exact same relative timeslot millions of times to accumulate suffi-cient signal. The resulting time resolutionis 1.71 ps, so any activity spanning less
than 0.5 mm in size would be difficult torecord.
Raskar also sees a potential applicationin the development of better cameraflashes. “An ultimate dream is: How doyou create studiolike lighting from acompact flash? How can I take a portablecamera that has a tiny flash and createthe illusion that I have all these umbrellasand sport lights and so on?” Raskar said.“With our ultrafast imaging, we can actu-ally analyze how the photons are travel-ing through the world, and then we canrecreate a new photo by creating the illu-sion that the photons started somewhereelse.”
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Photonics Spectra March 2012
Transparency discovery could benefit LEDs, touch screensSANTA BARBARA, Calif. – Scientistshave uncovered the fundamental limita-tions of optical transparency in tin dioxide(SnO2), a common conducting oxide. The discovery could lead to more energyefficient photovoltaics, LEDs and LCDtouch screens.
Transparent conducting oxides are used as contacts in a variety of optoelec-tronic devices. These materials are uniquein that they conduct electricity while being transparent to visible light. For
optoelectronic devices to emit or absorblight, the electrical contacts at the top ofthe device must be optically transparent.Opaque metals and most transparent materials lack the balance between thesetwo characteristics to be functional for use in such technology.
Scientists in the Computational Materi-als Group at the University of California,Santa Barbara, have used cutting-edge calculation methods to identify the opticaltransparency limitations of SnO2.
Three beams of light (red for infrared, yellow for visible and violet for ultraviolet) travel through a layer ofSnO2. Absorption by the conduction electrons in the oxide reduces the intensity of the beams. Courtesy ofHartwin Peelaers, University of California, Santa Barbara.
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Conducting oxides strike a balance between transparency and conductivity because their wide bandgaps preventabsorption of visible light by excitation of electrons across the gap, according tothe researchers. At the same time, dopantatoms provide additional electrons in theconduction band that enable electrical conductivity. However, these free elec-trons can also absorb light by being ex-cited to higher conduction-band states.
“Direct absorption of visible light can-not occur in these materials because thenext available electron level is too high inenergy,” said Hartwin Peelaers, a postdoc-toral researcher and the lead author of the
WEST LAFAYETTE, Ind. – Arrays ofplasmonic nanoantennas can abruptlychange the phase of light, potentially en-abling more powerful microscopes, com-puters and telecommunications systems.
“By abruptly changing the phase, wecan dramatically modify how light propa-
gates, and that opens up the possibility of many potential applications,” saidVladimir Shalaev, scientific director ofnanophotonics at Purdue’s Birck Nano-technology Center and a distinguishedprofessor of electrical and computer engineering.
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Plasmonic nanoantennas promise optics with strange new abilities
paper. “But we found that more complexabsorption mechanisms, which also in-volve lattice vibrations, can be remarkablystrong.”
The group observed that SnO2 onlyweakly absorbs visible light, letting mostlight pass through and making it a usefultransparent contact. In their study, thetransparency of SnO2 declined when moving to other wavelength regions. Absorption was five times stronger forultraviolet light and 20 times strongerfor the infrared light used in telecom-munications.
“Every bit of light that gets absorbed reduces the efficiency of a solar cell or
LED,” said Chris Van de Walle, head ofthe research group and a professor of materials science. “Understanding whatcauses the absorption is essential for engineering improved materials to be used in more efficient devices.”
The findings appeared in AppliedPhysics Letters (doi: 10.1063/1.3671162).The research was supported as part of the UCSB Center for Energy Efficient Materials, an Energy Frontier ResearchCenter funded by the US Department ofEnergy, the Belgian American EducationalFoundation and the UCSB Materials Research Laboratory.
The nanoantennas are V-shaped goldstructures formed on top of a silicon layer. They are an example of metamate-rials, which typically include so-called plasmonic structures that conduct cloudsof electrons called plasmons. The anten-nas are 40 nm wide, and researchers
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have demonstrated that they can transmitlight through an ultrathin plasmonicnanoantenna layer about 50 timessmaller than the wavelength of light it is transmitting.
“This ultrathin layer of plasmonicnanoantennas makes the phase of lightchange strongly and abruptly, causinglight to change its propagation direction,as required by the momentum conserva-tion for light passing through the inter-face between materials,” Shalaev said.
The work extends findings by scientistsled by Federico Capasso, the Robert L.Wallace Professor of Applied Physics andthe Vinton Hayes Senior Research Fellowin Electrical Engineering at HarvardSchool of Engineering and Applied Sci-ences. In that work, described in an Octo-ber 2011 Science paper, the researchersmodified Snell’s law, a long-held formulaused to describe how light reflects and re-
fracts while passing from one material into another.
Until now, Snell’s law had implied thatwhen light passes from one material to an-other, there are no abrupt phase changesalong the interface between the materials.The Harvard researchers’ experiments,however, showed that the phase of lightand the propagation direction could bechanged dramatically by using metamate-rials, which in this case were based on anarray of antennas.
“The near-infrared, specifically a wave-length of 1.5 microns, is essential fortelecommunications,” Shalaev said. “In-formation is transmitted across opticalfibers using this wavelength, which makesthis innovation potentially practical for advances in telecommunications.”
The Harvard researchers predicted howto modify Snell’s law and demonstratedthe principle at one wavelength; the Pur-
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Photonics Spectra March 2012
(Upper left) This schematic shows an array of gold plasmonic nanoantennas that can precisely manipulate light in new ways, a technology that could make possible optical innovations including more powerful microscopes, telecommunications and computers. (Upper right) A scanning electron microscope image of the structures. (Bottom) The experimentally measured refraction angle versus incidence angle for light demon-strates how nanoantennas alter the refraction. Courtesy of Purdue University Birck Nanotechnology Center.
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due researchers took the work a step further, creating arrays ofnanoantennas and changing the phase and propagation directionof light over a broad range of near-infrared light. The wavelengthsize manipulated by the antennas in the Purdue experimentranged from 1 to 1.9 μm.
“We have extended the Harvard team’s applications to thenear-infrared, which is important, and we also showed that it’snot a single-frequency effect; it’s a very broadband effect,” Sha-laev said, adding that having a broadband effect could enable avariety of technological applications.
The innovation, published online in Science (doi: 10.1126/science.1214686), could bring technologies for steering and shap-ing laser beams for military and communications applications,nanocircuits for light-based computers, and new microscopelenses.
Critical to the advance is the ability to alter light so that it ex-hibits “anomalous” behavior: It bends in ways not possible usingconventional materials by radically altering its refraction, aprocess that occurs as electromagnetic waves bend when passingfrom one material into another. Scientists measure this bending ofradiation by its index of refraction. All natural materials, such asglass, air and water, have positive refractive indices.
However, the nanoantenna arrays can cause light to bend in awide range of angles, including negative angles of refraction.
“Importantly, such dramatic deviation from the conventionalSnell’s law governing reflection and refraction occurs when lightpasses through structures that are actually much thinner than thewidth of the light’s wavelengths, which is not possible using nat-ural materials,” Shalaev said. “Also, not only the bending effect,refraction, but also the reflection of light can be dramaticallymodified by the antenna arrays on the interface, as the experi-ments showed.”
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Photonics Spectra March 2012
Vladimir Shalaev’s presentation from a webinar on the future of optics is availableon demand at www.photonics.com/Webinar.aspx?WebinarID=11
Breaking wavelength limits enables chips with finer featuresCAMBRIDGE, Mass. – A new way to break through wavelength-related limits to feature size in state-of-the-art silicon chips couldenable further leaps in computational power.
The microchip revolution has seen a steady shrinking of fea-tures on silicon chips, packing in more transistors and wires toboost their speed and data capacity. But in recent years, the tech-nologies behind these chips have begun to bump up against fun-damental limits, such as the wavelengths of light used for criticalsteps in their manufacture.
The new technique allows the production of complex shapesrather than just lines and can be carried out using less expensivelight sources and conventional chip-manufacturing equipment,said Trisha Andrew of MIT’s Research Laboratory of Electronics.
“The whole optical setup is on a par with what’s out there [inchip-making plants],” she said. “We’ve demonstrated a way tomake everything cheaper.”
In 2009, Andrew’s team described a way of creating finerlines on chips, dubbed absorbance modulation. As in the earlier
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work, the new system relies on a combi-nation of approaches: namely, interferencepatterns between two light sources and a material that changes color when illuminated.
But, Andrew said, a new step is the ad-dition of a photoresist, which produces apattern on a chip via a chemical changefollowing light exposure. The patterntransferred to the chip can then be etchedaway with a chemical developer, leaving amask that can control where light passesthrough that layer.
Although traditional photolithography is limited to producing chip features largerthan the wavelength of the light used, themethod devised by Andrew and her col-leagues has produced features one-eighththat size. Others have achieved similarsizes, she said, but only with equipmentwhose complexity is incompatible withquick, inexpensive manufacturingprocesses.
The new system uses “a materials approach, combined with sophisticated optics, to get large-scale patterning,” shesaid, adding that the technique should
make it possible to reduce the size of thelines even further.
The key to beating the limits usuallyimposed by the wavelength of light andthe size of the optical system is an effectcalled stimulated emission depletion
(STED) imaging, which uses fluorescentmaterials that emit light when illuminatedby a laser beam. If the power of the laserfalls below a certain level, the fluores-cence stops, leaving a dark patch. It turnsout that, by carefully controlling thelaser’s power, it is possible to leave a darkpatch much smaller than the wavelengthof the laser light itself. And by using thedark areas as a mask and sweeping thebeam across the chip surface to create apattern, these smaller sizes can be “lockedin” to the surface.
That process has been used to improvethe resolution of optical microscopes, butresearchers had thought it inapplicable tophotolithographic chip making. The inno-vation by Andrew and her colleagues wasto combine STED with the earlier ab-sorbance modulation technique, replacingthe fluorescent materials with a polymerwhose molecules change shape in re-sponse to specific wavelengths.
The technique not only can enable themanufacture of chips with finer features,but also could be used in advanced tech-nologies such as the production of pho-
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TECHNEWS
Photonics Spectra March 2012
Trisha Andrew and her colleagues have developeda way to create reduced feature sizes on siliconchips. Courtesy of M. Scott Brauer.
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tonic devices that use patterns to controlthe flow of light, rather than the flow ofelectricity. “It can be used for any processthat uses optical lithography,” Andrewsaid.
The results were published in PhysicalReview Letters (10.1103/PhysRevLett.107.205501).
The work is “strikingly simple and ele-gant” and “a most impressive demonstra-tion of the idea of using photochromicmolecules to create features that are bothfiner and closer together than half thewavelength of the light,” said the creatorof STED, Stefan Hell of Max Planck Insti-tute for Biophysical Chemistry in Göttin-gen, Germany.
“The work shows a concrete pathway to creating tiny and dense features at thenanoscale,” Hell added. “Because of itsfuture potential, it needs to be activelypursued.”
CHAMPAIGN, Ill. – A method that chem-ically etches patterned arrays in galliumarsenide will make high-end optoelec-tronic devices easier to manufacture.
Developed by a team led by Xiuling Liof the University of Illinois, the techniquewill enable faster, less expensive galliumarsenide-based devices such as solar cells,lasers, LEDs, field effect transistors, ca-pacitors and sensors.
The physical properties of a semicon-ductor can vary depending onits structure, so a semicon-ductor wafer must be etchedto tune its electro-opticalproperties and connectivitybefore it is assembled intochips. Wet etching uses achemical solution to erodethe semiconductor in all directions, and dry etchinguses a directed beam of ions to bombard the surface, carving out a directed pattern.
Although silicon is the most commonmaterial in semiconductor devices, materi-als in the III-V group are more efficient in optoelectronic applications, such assolar cells or lasers. Unfortunately, all of these materials can be difficult to dry-etch because high-energy ion blasts candamage the semiconductor’s surface. III-V semiconductors are especially susceptible to damage.
To address this problem, the researchers
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For more information on Andrew’s earlier work, see “Narrower Chip Patterns Made”
at http://www.photonics.com/a37074.
Semiconductor etching gets easier
Scanning electron microscope image of nanopillars etched in gallium arsenide via metal-assisted chemical etching. Images courtesy of Xiuling Li.
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used metal-assisted chemical etching(MacEtch), a wet-etching approach theyhad developed for silicon. Unlike otherwet methods, MacEtch works in one di-rection, from the top down. It is faster andless expensive than many dry-etch tech-niques, Li said. Her group optimized theMacEtch chemical solution and reactionconditions for the III-V semiconductorgallium arsenide (GaAs).
The process involves patterning a thinfilm of metal onto the GaAs surface, thenimmersing the metal pattern into the Mac-Etch chemical solution. The metal cat-alyzes the reaction so that only the areastouching metal are etched away, and high-aspect-ratio structures are formed as themetal sinks into the wafer. When the etch-ing is done, the metal can be cleaned fromthe surface without damaging it.
Realization of high-aspect-ratio III-Vnanostructure arrays by wet etching cantransform the fabrication of semiconductorlasers where surface grating is fabricatedby dry etching, which is expensive andcauses surface damage,” Li said.
Li’s group used a patterning technique
developed by John Rogers, a professor ofmaterials science and engineering at theuniversity. The two research teams collab-orated to optimize the method, called softlithography, for chemical compatibilitywhile protecting the GaAs surface. Soft lithography is applied to the whole semi-conductor wafer, as opposed to small seg-ments, creating patterns over large areas –without expensive optical equipment.
By using soft lithography and MacEtchtogether, the teams produced large-area,high-aspect-ratio III-V nanostructures at a
minimal cost, Li said. The technique waspublished in Nano Letters (doi: 10.1021/nl202708d).
Next, the researchers hope to furtheroptimize conditions for GaAs etching andto establish parameters for MacEtch ofother III-V semiconductors. They hope todemonstrate device fabrication, includingdistributed Bragg reflector lasers and pho-tonic crystals.
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Photonics Spectra March 2012
Ashley N. [email protected]
Melinda A. [email protected]
Metal-assisted chemical etching uses two steps. First,a thin layer of gold is patterned on top of a semi-conductor wafer using soft lithography (left). Thegold catalyzes a chemical reaction that etches thesemiconductor from the top down, creating 3-Dstructures for optoelectronic applications (right).
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The impact of Thailand’s epic flood continues into 2012BANGKOK – Flooding that began morethan four months ago continues to affectthe optical components industry, as amajor supplier reported a revenue declineof nearly 50 percent for the second quarterof fiscal 2012 and continues to move cus-tomers out of a still-flooded facility thatmay never reopen.
The disaster began last July after unusu-ally heavy monsoon rains, killing hun-dreds and flooding from Chiang Mai inthe north to parts of the capital city ofBangkok near the mouth of the ChaoPhraya River. Waters began infiltrating
industrial manufacturing facilities nearBangkok in the fall. The event, estimatedby the World Bank to have cost $45 bil-lion, now ranks as the world’s fourthcostliest, surpassed only by the 2011earthquake and tsunami in Japan, the 1995Kobe earthquake and Hurricane Katrina.
Fabrinet, a major provider of opticalcommunications components, modulesand subsystems, industrial lasers, and sensors for companies such as Oclaro, In-finera, JDSU and Opnext, has its facilitiesin Bangkok. Its customer base includesoptical communications, industrial lasers
and sensors OEMs that provide productsto the semiconductor processing, biotech-nology, metrology, materials processing,automotive and medical device markets.
On Oct. 24, 3.5 feet of water infiltratedseveral manufacturing buildings at Fab-rinet’s Chokchai campus in Pathum Thani.The facility had accounted for between 30and 40 percent of the company’s revenue;the company does not have manufacturingcapabilities outside of Thailand.
Water was pumped out of Chokchaibuildings as of Nov. 29, and while levelsoutside the walls surrounding the plant
36 Photonics Spectra March 2012
TRACKFAST
The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite acquired these natural-color images of Ayutthaya, north of Bangkok, on July 11, 2011 (left) and Oct. 23, 2011 (right). In both images, the Chao Phraya River curves through the southwestern part of the city (image lower left). Thailand’s monsoons generally last from mid-May to September. However, the large expanse of floodwater in October 2011 is unusual, even in monsoon season. (NASA Earth Observatory image created by Jesse Allen and Robert Simmon, using EO-1. ALI data provided courtesy of the NASA EO-1 team and the US Geological Survey.)
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continued to recede, they remained at 2.5 feet high.
Fabrinet says it may never again manu-facture at the Chokchai campus; instead, it will divert manufacturing seven milesnorth to existing buildings 3, 4 and 5 at its Pinehurst campus and to its neweststructure there, building 6, upon comple-tion. Pinehurst experienced minimal im-pact from the flooding.
Completing building 6 is the primarydriver of its near-term plans to boost ca-pacity, said John Marchetti, Fabrinet chiefstrategy officer, in a Feb. 6 earnings callwith investors.
“We have met our initial objectives andnow have 11 manufacturing bays repre-senting 80,000 square feet open and ramp-ing with customer projects migrating fromChokchai,” he said. “Our next step is tocomplete the entire 300,000-sq-ft building,which includes engineering and officespace, by the end of March.”
Upon completion, the capacity of build-ing 6 will be more than sufficient to houseall customer products from Chokchai andleave room to ramp production of addi-tional projects from new and existing customers, Marchetti said.
Fabrinet reported total revenue of $186million for the first quarter of fiscal 2012,which ended Sept. 30, 2011, an increase ofmore than 7 percent year-over-year. TheChokchai site accounted for 29 percent ofits first-quarter revenue and Pinehurst, for67 percent.
Flood-related expenses for the quarterwere $40.3 million, said Mark Schwartz,chief financial officer at Fabrinet. Inven-tory damage, both to Fabrinet and its cus-tomers, accounted for $26.2 million of the
total; $4.6 million was for damages to the company’s machinery and equipment, and the remaining $9.5 million stemmedfrom damage to its Chokchai campus andother flood-related expenses. Future flood-related losses are estimated to be between$44 million and $63 million.
Revenue for the second quarter, whichended Dec. 30, 2011, was down nearly 50percent, the company said. And achievingthe $96.6 million total was feasible “onlythrough the incredible effort of our em-ployees and the strong support from ourcustomers,” Schwartz said.
Revenue for its optical communicationssector was $68.4 million, or 70 percent ofthe total. Lasers, sensors and other rev-enue totaled $28.2 million, or nearly 30
percent. “Quarter over quarter, this repre-sents a decline of 50.3 percent in opticalcommunications and a decline of 42.2 per-cent in our lasers and sensors market, inboth cases driven by the impact of the October flood,” Schwartz said.
“I would expect the first quarter of2013, the September quarter, will likely bethe first quarter where we wouldn’t expectour revenues to be impacted as a result ofthe flood,” he said.
The company told investors it didn’t expect to lose customers permanentlyfrom the flooding, and CEO Tom Mitchelladded that Fabrinet had gained several in-dustrial optics customers in the last quar-ter, although he wasn’t at liberty to namethem.
37Photonics Spectra March 2012
Floodwaters affect multiple areas of Thailand during the humanitarian survey team’s aerial flood assessmentnorth of Bangkok on Oct. 16, 2011. US Marine Corps photo by Cpl. Robert J. Maurer.
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Fabrinet officials pointed out that someof the revenue decline is attributable to aweakening in the overall communicationsindustry. Regarding the industry overall,Marchetti commented, “We believe thatsteep order reductions witnessed in thepast year have given way to stability,along with some pockets of improvement… inventories are lean, overall industrydemand is stable to slightly improving,and our own supply capabilities arestrongly rebounding.”
Fabrinet’s customers, who are workingwith both their own insurance carriers andFabrinet’s toward reimbursement, also re-cently started announcing the impact ofthe continuing production slowdown ontheir quarterly revenue and estimatedyearly earnings.
“We expect full commercial productionby the end of March for three of our fiveaffected product lines and within the Junequarter for the remaining two,” said AlainCouder, chairman and CEO of Oclaro, aSan Jose, Calif.-based optical communica-tions and laser components provider, onJan. 26. Those product lines, which havemoved to Pinehurst, include high-powerlasers, amplifiers, tunable dispersion com-pensators, lithium niobate external modu-lators and wavelength-selective switchproducts.
For the second quarter of 2012, Oclaroreported revenue of $86.5 million, downfrom $105.8 million in the first quarter.
“Although our management cannot fullyquantify the possible impact of the flood-ing in Thailand on our business, the sup-ply disruption materially and adverselyimpacted our results of operations, includ-ing our revenue, for the second fiscalquarter of 2012, and will materially andadversely affect our results of operations… for at least the next two fiscal quar-ters,” Oclaro said in a late January SECfiling.
Oclaro said it expects to spend about $6 million in each of the second and thirdfiscal quarters. These amounts include thenecessary capital currently expected to re-cover product lines lost during the flood.
II-VI of Saxonburg, Pa., a maker oflaser optic materials, optics, componentsand electro-optical products, said in a Jan.24 second-quarter fiscal 2012 earnings callthat the flooding significantly impactedAegis Lightwave, a tunable optical devicemaker it acquired in July 2011. Aegis is aFabrinet customer at the Chokchai campus.
“The loss in production capacity … was
significant with Aegis’ revenue in the December quarter decreasing by about 40percent compared to the September quar-ter,” said II-VI Chief Financial OfficerCraig A. Creaturo during the call.
It will be late in the fourth quarter be-fore Aegis production returns to pre-floodlevels, II-VI President and CEO Francis J.Kramer said.
Fremont, Calif.-based Opnext, a sup-plier of optical products and systemsformed out of Hitachi, reported on Feb. 7that revenue for its third fiscal quarter was down 38.3 percent sequentially to $53 million due to the loss of productioncapacity at Fabrinet.
“During the quarter, we started limitedassembly and testing of our 10G modulesat our facilities in Japan and California,and we plan to restart manufacturing inThailand at Fabrinet’s Pinehurst campusthis month, with a return to pre-flood pro-duction capacity expected by March 31,2012,” said Opnext CEO Harry Bosco in a statement. Opnext supplies the commu-nications, defense, security and biomedicalindustries.
At the time of the flooding, the com-pany’s production equipment at theChokchai facility included the 10-Gb/smodule test sets, which originally costmore than $31 million. Opnext also hadabout $16 million of inventory with Fab-rinet, including $7.6 million in raw materi-als and $8.1 million in finished products.
Fabrinet has allocated surface-mounttechnology lines at Pinehurst to Opnext,
and new test systems are being con-structed to replace systems lost, Opnextsaid in December.
The lost production at Fabrinet willhave a “significant impact” on its opera-tions for the remainder of the current fis-cal year, which ends March 31, 2012, thecompany said.
Fabrinet has historically accounted formore than 50 percent of its fiber optics-related revenue, Emcore Corp. said in Oc-tober, when floodwaters submerged mostof its manufacturing and test equipment aswell as its inventory.
In a first-quarter earnings call on Feb. 14, Emcore said revenue totaled$37.5 million, a decrease of $14.7 millionresulting primarily from the decline infiber optics revenue impacted by theflood. The fiber optics segment’s revenuedecreased about $12.6 million from theprior quarter due to the flooding, account-ing for $18.4 million, or 49 percent, of thecompany’s total revenue. Its photovoltaicssegment was not affected.
Its recorded losses for the quarter attrib-uted to the flood were $5.7 million, withthe majority due to destroyed inventory.
Emcore has implemented alternativemanufacturing plans at its facilities inChina and the US. It also has been focus-ing on rebuilding its high-volume manu-facturing infrastructure at other Thailandlocations, with support from Fabrinet andits own manufacturing facility in China.
38
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Optics industry on steady ground after quakeTOKYO – One year after the devastatingtsunami and earthquake in Japan, there areno lasting effects on the optics industry,and all supply chain problems have beenresolved, according to two executivesfrom Edmund Optics Japan Co. Ltd.
The 9.0-magnitude quake that hit onMarch 11, 2011, was the fourth largest inthe world since 1900 and the largest inJapan since modern records of such events
began being kept 130 years ago. Nearly16,000 people died, and the World Bank’sestimated economic cost was $235 billion,making it the most expensive natural dis-aster to date. The quake struck about 80miles east of Sendai in Honshu, about 231miles northeast of Tokyo.
“The majority of the optics industry inJapan is not located within the tsunamizone,” said Timothy Paul Kennedy, sales
For more information, see the articles “Thailand Flooding Hits Optics Industry” at
photonics.com/ a48923 and “II-VI Acquires AegisLightwave” at photonics.com/a47580.
Melinda A. [email protected]
312_FastTrack_Layout 1 2/22/12 4:14 PM Page 38
director at Edmund Optics Japan. Shortly after the quake, Edmund Optics
said it did not suffer any major structuraldamage and was considering transferringsome of its work to its Singapore andPennsburg, Pa., facilities. HamamatsuPhotonics also expected problems to besupply chain-based, but anticipated onlyminor delays.
“For most of the manufacturing acrossJapan, the quake only affected the logis-tics, which was back on regular schedulewithin roughly three to six weeks,”Kennedy said.
The optics industry in Japan beganmore than 100 years ago when an opticalresearch lab opened in Tokyo in 1906.Since it began producing rangefinders dur-ing World War I, the industry has growninto the research and manufacture of pre-cision glass, filters, coatings, aspheres,electro-optics and precision optical assem-blies, among others. (For more on why optics manufacturing in Japan is still rele-vant, see the September 2010 article inPhotonics Spectra, page 48.)
The majority of supply issues resultingfrom the quake were mainly in the digitalcamera, automotive and memory devicemarkets, as well as some other industries,Kennedy said, but even in those industries,companies were able to qualify secondsources that ramped up production quicklyto meet demand and reduce delays.
“We have not seen many customersmoving away from the Japanese market,”said Kaz Shibata, senior sales manager atEdmund Optics Japan. “However, manyJapanese companies are considering movingmore of the low-end production overseas.”That’s not a result of the tsunami, he added,but rather of the strong Japanese yen.
“Due to problems in other parts of theworld, such as the floods in Thailand,Japan has planned to move many factoriesfrom Thailand back to Japan while alsoconsidering moving to other areas,” Shi-bata said.
Because of the high value of the yen,many companies have a good opportunitynow to buy space outside of Japan forlower-precision products, he said. “Thiswill continue to fuel the need for Japan tospend on R&D for next-generation tech-nologies, while keeping the precision pro-duction in Japan.”
“Although Japan suffered such a devas-tating event, the Japanese people reactedquickly to ensure the business supply con-tinued,” Kennedy said.
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Ashley N. [email protected]
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ROCHESTER, N.Y. – The company thatcreated the first digital camera said it willphase out its digital device business in thefirst half of this year.
“For some time, Kodak’s strategy hasbeen to improve margins in the capturedevice business by narrowing our partici-pation in terms of product portfolio, geog-raphies and retail outlets,” said PradeepJotwani, president, Consumer Businesses,and Kodak chief marketing officer.
Troubled Eastman Kodak Co., whichfiled for bankruptcy on Jan. 19, said thephaseout will save it more than $100 mil-lion a year.
The 132-year-old company, which oncecontrolled the photographic film market,has been on a slow, painful decline foryears, closing 13 manufacturing plants and 130 processing labs and reducing its workforce by 47,000 since 2003. It lost 88 percent of its value last year. At itspeak in 1997, Kodak’s stock was valued at nearly $30 billion. Today it stands at
less than $145 million, according to TheWall Street Journal.
Shortly before filing for bankruptcy, thecompany said it was cutting its businesssegments from three to two to reducecosts.
In 1975, Kodak employee Steven Sas-son developed the first digital camera prototype, which weighed eight poundsand was about the size of a toaster. Overthe next three decades, Kodak amassed a portfolio of more than 1100 digital imaging patents.
The company has had no luck trying to find a buyer for those patents, which itsaid have generated more than $3 billionin licensing revenue since 2003. Kodakalso filed a number of suits in Januaryagainst companies such as Apple, Re-search in Motion Ltd. and Fujifilm Corp.for infringing those digital patents.
Kodak’s potential demise was on theminds of many at SPIE Photonics West2012, held in January in San Francisco.
“The collapse of one of our industry giants should be of concern to all of us,”said Robert Edmund, CEO of EdmundOptics at an executive panel on optics andphotonics. “There are lessons here for allof us.”
Michael J. Cumbo, president of IdexCorp.’s optics and photonics platform,began his career at Eastman Kodak. He said that the company didn’t move fast enough to capitalize on its digitaltechnology because it was reluctant to render obsolete its photographic film business, which had a profit margin of 75 percent.
“Kodak’s failure had lots of reasons, notjust a lack of ability to manage products,”said Ken Kaufmann, vice president ofmarketing at Hamamatsu. He added that,as a major employer in a small town,Kodak had an “ethical and moral responsi-bility” to keep employees.
The economy of Rochester is muchmore diverse than it was in the early 1980s
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Kodak to delete its digital device division
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when it relied on Xerox, Kodak andBausch & Lomb for the majority of employment opportunities, said DuncanMoore in a Rochester Democrat & Chronicle op-ed piece in February. He isvice provost for entrepreneurship and theRudolf and Hilda Kingslake Professor ofOptical Engineering at the University ofRochester. While Kodak shed 54,000 jobsover the past three decades, the communitygained a net of 100,000 jobs in industriessuch as manufacturing, business, services,
construction and higher education. The University of Rochester, with its
medical center, is the area’s largest em-ployer, Moore said and, since 1996, 51startups have been created based on theuniversity’s technologies.
The challenge now is to head off a“brain drain” of twenty-somethings out ofthe area, Moore told Photonics Spectra.
“Both Kodak and Xerox had nationalrecruiting of twenty-somethings toRochester,” Moore said. “That’s not hap-
pening now. The challenge as a commu-nity is how do we get the 70,000-plus stu-dents in the area universities to embraceour area and stay?”
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Ashley N. [email protected]
BUSINESSBRIEFS
Association Changes Name To more accu-rately reflect its mission, the umbrella trade as-sociation Automation Technologies Council haschanged its name to the Association for Ad-vancing Automation (A3). Comprising the Robotic Industries, Automated Imaging and Motion Control associations, the entity is an advocate for the benefits of automation. WithinA3, the associations will continue to focus onhow companies and organizations specificallycan apply robots, vision and motion control. The A3 board of directors consists of industryleaders from motion control, vision and roboticscompanies.
IPG Photonics Adding Jobs With the help of $1.7 million in tax credits from the state ofMassachusetts, IPG Photonics will add 175 employees as part of an $18 million plan to expand its facility by more than 100,000 sq ft.Lt. Gov. Timothy Murray joined state and localofficials at the fiber laser maker’s Oxford facil-ity to announce both the tax credit under the Economic Development Incentive Program anda $2.2 million MassWorks Infrastructure Grantfor the town of Oxford. Oxford, with the supportof other towns, will use the funds to install asewer extension to open areas for economic development.
Raytheon Wins Defense Contracts RaytheonCo. of Waltham, Mass., has been awarded$13.4 million by DARPA to develop a manufac-turing process that will make thermal imagersmore affordable for military use. Under thethree-year contract, Raytheon Vision Systems ofGoleta, Calif., will develop wafer-scale manu-facturing processes to reduce the size, weight,power and cost of thermal cameras so that theycan be integrated into cell phones and otherportable electronics. Wider availability wouldenhance situational awareness and informationsharing among dismounted soldiers and individ-ual intelligence personnel, where a common
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view of the battlefield is critical.Also, in support of Blackhawk helicopter oper-
ations, the US Army has awarded Raytheon Co.a $14.6 million contract to develop new imageprocessing technology for the Advanced Distrib-uted Aperture System (ADAS). The system is amultispectral technology that gives helicopter pilots 360° situational awareness, improving aircraft and crew survivability when operating in low-visibility conditions. The new processorwill significantly enhance the system’s high-res-olution imagery. The technology upgrade in-
cludes thermal cameras and a next-generationhelmet-mounted display subsystem.
In April 2011, Raytheon successfully completedthe integration of ADAS capabilities required bythe US Department of Defense’s Joint CapabilityTechnology Demonstrations program.
Mobius Photonics Receives Patent MobiusPhotonics Inc. has been granted US Patent No.8,009,705 for an optical fiber-based master os-cillator power amplifier system that avoids stim-ulated Brillouin scattering, a spontaneous phe-
nomenon of light scattering that occurs in opti-cal fibers, reducing a fiber laser system’s opticalpower. To overcome this, Mobius developed amethod that enables systems to produce high-peak-power square pulses that are efficientlyconverted to desired wavelengths. The inventionis suitable for applications such as materialsprocessing that demand robust fiber-based sys-tems that can produce high-quality, high-peak-power green or ultraviolet pulses.
FEI Acquires Aspex FEI Co. of Hillsboro, Ore.,has paid $30.5 million for Aspex Corp. of Del-mont, Pa., which makes scanning electron mi-croscopes for environmentally demanding mili-tary, industrial and factory floor applications.Aspex makes an electron microscope that ispaired with FEI’s software as part of the QEM-SCAN WellSite product FEI markets to the oiland gas industries. FEI now owns the hardwareand software that have contributed to its growthin the natural resources market. Aspex gener-ated $10 million in sales for the fiscal year end-ing June 30, 2011.
Osram Develops GaN-Based LEDs on Silicon To replace the sapphire substrates com-monly used in the LED industry, researchers atOsram Opto Semiconductors have manufac-tured blue and white LED prototypes in whichgallium-nitride layers are grown on 6-in. siliconwafers. The new chips, which are already in thepilot stage, are being tested under practicalconditions, and Osram said they could be com-mercially available in about two years. Silicon isan attractive, low-cost option for large-volumefabrication. Quality and performance data onthe fabricated LED silicon chips match those ofsapphire-based chips. The company is a sub-sidiary of Osram AG of Munich.
PD-LD Granted Patent Specialty photonicspackaging company PD-LD Inc. of Pennington,N.J., has received US Patent No. 7,982,869,which protects the use of dual laser sources forthe analysis of a single substance. The tech-nique, based on proprietary VBG (volume Bragggrating) laser wavelength stabilization, providesthe underlying mechanism for shifted excitationRaman differential spectroscopy, an analyticaltechnique that the company says represents asignificant development in the capabilities ofRaman spectroscopy. CEO Vladimir Ban saidthat the patent will allow PD-LD to offer Ramanexcitation sources that extend portable and lab-based instruments.
Materion Expands Capacity Materion Micro-electronics & Services, a unit of Materion Corp.of Mayfield Heights, Ohio, has completed a 50percent capacity expansion of its Wheatfield,N.Y., facility. The site provides precision partscleaning and surface treatment of physicalvapor deposition shield kits for manufacturers of photovoltaics, medical consumables, LEDsand wireless products. The expansion includes afully automated robotic twin wire arc spray, newcleaning processes, increased precious metalsrefining capacity and a Class 10,000 certifiedcleanroom. Materion, through its wholly ownedsubsidiaries, supplies advanced enabling mate-rials such as specialty metals, coatings and en-gineered beryllium alloys.
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AQT Solar Secures Funding AQT Solar ofSunnyvale, Calif., has acquired $18.7 million inventure funding to deploy a second line of cop-per indium gallium diselenide (CIGS) thin-filmsolar cells. The Series B investment, which wasmore than the company received for its firstround of funding, brings the total capital it hasattracted to almost $40 million. This fundinground follows a year of consistent progress andgrowth for AQT, the company said. The CIGS2.0 technology line allows for continuous in-lineproduction, simplifying and streamlining themanufacturing process. The process has re-sulted in the development, shipment and scal-ing of CIGS module products in just four years.
Incom Buys Paradigm Optics Fused fiber op-tics components maker Incom Inc. of Charlton,Mass., has expanded into the polymer fiber op-tics market with the acquisition of Vancouver,Wash.-based Paradigm Optics. Financial detailsof the transaction were not disclosed. ParadigmOptics makes polymer fiber optic devices. Thecompany will be folded into Incom’s operations,which manufacture fiber optics for scientific,medical, defense and life sciences applications.Company President and CEO David Welker willremain as director, working under Incom Presi-dent and CEO Michael Detarando.
General Dynamics Creates Imaging Divi-sion General Dynamics Advanced InformationSystems of Fairfax, Va., has created General
Dynamics Global Imaging Technologies to deliver imaging solutions for law enforcement,defense and homeland security customers. The new division will allow the company to add integrated long-range infrared and high-definition (HD) imaging systems to its portfolioof electro-optical infrared cameras, precisionoptical components, stabilized HD gimbals and motion control products. The new productsare expected to address applications that de-mand detailed optical surfaces, high-accuracyimage stabilization and tight motion control tol-erances, such as remotely operated weaponssystems, imaging telescopes and long-rangesurveillance cameras.
Novotech Completes Modernization Plan In-frared optics and germanium materials supplierNovotech Inc. of Acton, Mass., has completedan equipment modernization plan that includesthe purchase of automated robotic optics edg-ing and curve-generating machines that canproduce several thousand units per day. In ad-dition, Novotech said, a computer numericalcontrol polishing machine from OptiPro Systemsof Ontario, N.Y., can handle large-size windowsand lenses up to 200 mm in diameter. Severalsaws manufactured by the former Silicon Tech-nologies Corp. were upgraded with numericalcontrollers, and two additional inner diametersaws were delivered. Also, a Precitech diamondturning machine was upgraded with the HS75high-speed spindle.
Precision Optical Opens Facility Laser-qualityprecision optical assemblies and componentsmanufacturer Precision Optical of Costa Mesa,Calif., celebrated the opening of its 42,000-sq-ft facility in early December. Members of theoptics industry, local government officials, andmembers of local business and civic groups at-tended the ceremony. Speakers included AlanLambert Sr., chairman and CEO of PrecisionOptical, and Roderick Randolph, president andchief operating officer. Randolph spoke of plansto grow and expand the company’s productbase by offering lens manufacturing and assem-bly, and infrared optics and coatings.
Ametek Buys TMC Electronic instrumentsmaker Ametek Inc. of Berwyn, Pa., has ac-quired privately held Technical ManufacturingCorp. (TMC) of Peabody, Mass., a manufacturerof vibration isolation systems and optical testbenches. Financial terms were not disclosed.TMC’s products are used to isolate highly sensitive instruments such as scanning electron microscopes and ultraprecision machine tools for the microelectronics, life sciences, photonics and ultraprecision manufac-turing industries. The company also suppliespassive vibration cancellation systems, opticaltest tables, and acoustic and magnetic isolationhoods. TMC has estimated annual sales of $30 million. It will become part of Ametek Electronic Instrument Group’s Ultra PrecisionTechnologies Div.
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GreenLight
Solar concentration without mirrors
M irror-free thermophotovoltaic devices could someday make amuch simpler and less expensive
system to concentrate sunlight. The goal isto prevent heat from escaping the thermo-electric material by using a photonic crys-tal – essentially, an array of preciselyspaced microscopic holes in a top layer of the material.
By concentrating the sunlight thermally– capturing it and reflecting it back intothe material – the device could absorb asmuch heat as a standard black object, yetnot reradiate much of the heat, suggestsPeter Bermel, a scientist at MIT’s Re-search Laboratory of Electronics.
Infrared radiation from the sun couldenter the device through the holes on thesurface, but the reflected rays would be
blocked when they try to escape; this ismuch like the Earth’s greenhouse effect.The blockage is achieved with a preciselydesigned geometry that allows only thoserays that fall within a very tiny range ofangles to escape, while the rest stay in thematerial and heat it up – theoretically, tovery high temperatures.
In direct sunlight, an ordinary dark-colored, light- and heat-absorbing materialcan’t get much hotter than boiling waterbecause the object reradiates heat almostas fast as it absorbs it; power generationrequires higher temperatures than that. Byconcentrating sunlight with parabolic mir-rors or a large array of flat mirrors, muchhigher temperatures are possible, but atthe expense of a much larger and morecomplex system.
Bermel said that such a system “at largescale, is efficient enough to compete withmore conventional forms of power. This is an alternative to concentrators.”
The efficiency of ordinary solar-energy-harnessing systems is around 10 percent,but the new theoretical material couldachieve 32 to 36 percent. It is important tonote that an increase in efficiency of even1 percent is considered significant.
The system is simple to manufacture,using standard chip-fabrication technol-ogy, Bermel said. By contrast, the mirrorsused for traditional concentrating systemsrequire extremely good optics, which areexpensive.
The advance envisions the use of exist-ing light-absorbing material to create aphotonic structure that preferentially emitslight in a direction and wavelength rangeoptimal for photovoltaic conversion, saidJason Fleischer, an associate professor ofelectrical engineering at Princeton Univer-sity in New Jersey, who was not involvedin this work.
Doing so, Fleischer said, “increases theefficiency significantly beyond classicalpredictions based on unconcentrated sun-light, enabling a small device to generateas much electricity as a conventional onethat is much larger.”
The heat-trapping device was describedin Nanoscale Research Letters (doi:10.1186/1556-276X-6-549). l
45Photonics Spectra March 2012
A diagram of an angle-selective solar thermophotovoltaic system. Courtesy of P. Bermel et al, Nanoscale Research Letters 2011 6:549.
A novel heat-trappingsystem could bring
photovoltaic efficiency to as high as 36 percent.
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47Photonics Spectra March 2012
Lessons learned from a recent laser accidentBY MICHAEL B. WOODSSLAC NATIONAL ACCELERATOR LABORATORY
In September 2009, a graduate studentworking at SLAC suffered a laser eyeinjury while adjusting a polarizing
beamsplitter being used with a femto-second Ti:sapphire laser.1 The laser parameters were 800-nm wavelength, 100-fs pulse width, 1-kHz repetition rateand 100-mW beam power.
The polarizing beamsplitter, P1, waspart of an optics configuration used for intensity control (Figure 1). During ad-justment of the P1 optic, an unblocked reflected beam – the dashed beam in Figure 1 – hit the laser operator’s eye. Although the standard operating proceduredocument and the area warning signsspecified that laser eyewear protection(LEP) was required for this work, the op-erator was not wearing any at the time ofthe accident, resulting in a small blindspot sustained in the peripheral vision re-gion. Fortunately, the damage was rela-tively minor, but the incident could haveresulted in significant vision impairment.
The P1 polarizer optic has three compo-nents: a polarizer cube, which has an es-cape window for the reflection of one po-larization component (the polarizer trans-mits one of the two linear polarizationstates and reflects the other); a beam tube,which also has an escape window; and arotation mount. The reflected beam fromP1 was not used in the experiment, and,initially, the beam tube and polarizer werecorrectly secured in the rotation mountwith the tube blocking the reflected beam.
The laser operator wanted good extinc-tion capability for laser intensity controland needed the polarizer optics to be nor-mal to the beam path. The operator ob-served the backreflection from P1 on afluorescent card while wearing LEP butthought the position information was notprecise enough because of a blooming ef-fect resulting from saturation on the card.The operator removed the LEP to allowviewing of the backreflected beam on awhite card. The operator also wanted toalign the polarizer axis with a 0° marking
on its rotation mount, and loosened thepolarizer and associated beam tube in therotation mount to allow this adjustment.While doing so, the escape windows forthe polarizer and beam tube accidentallybecame aligned, allowing the unblockedreflected beam to come up out of the hori-zontal plane directly into one eye.
Direct causesThe direct causes of the accident were
deficiencies in administrative alignmentprocedures, failure to wear LEP and defi-ciencies in engineering controls.
Two engineering controls, or configura-tion changes, that would have preventedthe accident are: 1) using beam tubes withno escape window, and 2) using nonrotat-ing mounts for the polarizing beamsplit-ters. The beamsplitters would then bemounted so that the reflected beam wouldbe in the horizontal plane only (using λ/2as needed to rotate the polarization vectorof the incident laser beam).
Significant mistakes were made in ad-ministrative alignment procedures. Goodalignment practices would include the fol-lowing:• For aligning an optic normal to the
beam, choose a method where LEP isworn, such as centering an iris on the in-cident beam and using a CCD camera orIR viewer to see the backreflected beamfrom the optic being aligned.
• Block or disable laser beams when notneeded. The accident occurred when theworker was rotating the polarizer in itsmount, which did not require the beam.Proper protocol would require blockingthe beam before adjusting the optic.
• Do not perform unnecessary optics ad-justments near accessible laser beams.Installing the polarizer and adjusting itsangle in the rotation mount should havebeen done in an optics preparation areaaway from accessible laser beams.
Root causes, corrective actionsThe postaccident analysis determinedseven root causes: • Inadequate training: in particular, on-the-
job training (OJT).• Inadequate supervision.• Inadequate work planning.• Inadequate adherence to laboratory rules
for laser alignment. • Deceptive hazard of a dimly visible
800-nm beam.• Out-of-plane beams from a polarizer.• Inadequate intervention following (prior)
laser eyewear safety violations by otheroperators in the facility. (The injuredlaser operator had observed more seniorlaser operators remove required LEP toperform some tasks.) Actions were taken to address the direct
and root causes listed above, which in-cluded significant improvements to train-
LASERS IN USE
DBS P1 �/2 P2
e-ray
800 nm
o-ray
400 nm
Figure 1. Optics configuration associated with the accident. DBS � dichroic beamsplitter; �/2 � half- wave plate; o-ray = ordinary ray, and e-ray = extraordinary ray; and P1 and P2 = polarizers. Images courtesy of Michael Woods, SLAC National Accelerator Laboratory.
SAFETY PERSPECTIVES
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ing and supervision, and which directlyaddressed hazards associated with dimlyvisible beams and optics that generate out-of-plane beams.
SLAC had a laser supervisor trainingcourse at the time of the accident, although it was relatively new at that time. This course has been subsequentlystrengthened. It is a two-hour classroomcourse given by the laser safety officerand emphasizes responsibilities for supervisors.
Supervisor responsibilities include:• Providing good site-specific OJT. This
training requires a good syllabus andmust be documented. A template exam-ple for an OJT syllabus has been createdfor this.
• Communicating expectations for safe operations and accountability for actionsby laser operators.
• Conducting prejob briefings when appro-priate and encouraging laser operators torequest or conduct these; e.g., for new,
unfamiliar or infrequently performedtasks.
• Ensuring that the laser facility is wellmanaged, performing frequent facilityvisits and interacting with laser operatorsin their work.
• Effectively addressing problems as theyarise. This requires good understandingof a problem’s cause.
• Being proactive about improving proce-dures and acquiring new equipment toimprove operations and safety.
• Ensuring the availability of good equip-ment, procedures and laser eyewear; i.e.,making it easy to comply with lasersafety requirements.
• Modeling a good safety culture.
Two new training requirements havebeen added:• Laser Accidents & Lessons Learned.
This 90-minute course, taught by thelaser safety officer, reviews the SLACaccident as well as other accidents and
near-miss situations and how they can beavoided. SLAC’s eyewear policy and re-quirements for proper work planning andcontrol also are discussed.
• Laser Alignment Practical. This course2
takes one to three hours to complete. It isgiven by laser supervisors to a maximumof three students at a time. Standardizedpractical training is given in core lasersafety practices that are not site-specific.The course educates prospective laseroperators on safe alignment techniquesand common mistakes that are made. Italso assists supervisors in determiningthe student’s skill level and how muchsupervision will be needed. A schematicand photo of the training course setupare shown in Figures 2 and 3.
Two specific issues for the SLAC acci-dent are hazards associated with polarizingbeamsplitters and dimly visible 800-nmbeams.• Deceptive hazard of a dimly visible
48 Photonics Spectra March 2012
LASERS IN USE
Green DPSS Laser6.5 mW at 532 nm
Red HeNe Laser2 mW at 633 nm
IR D
iod
e L
aser
3.5
mW
at
785
nm
Blu
e D
iod
e L
aser
4 m
W a
t 40
5 n
m
TrainingPeriscope
(Insertable)
Filter 1 ODReduces output
to <0.34 mW(Class 2)
Filter 1 ODReduces output
to <0.4 mW(Class 1)
DiffractionGratingIrisEnd
MirrorIris
Flip-Up Mirror
Beam Block
Iris
FoldMirror 2
Polarizer(Insertable)
FoldMirror 1
Iris
Iris
�125 mmLens
�75 mmLens
FoldMirror 3
Periscope(Fixed)Zero-Order �/2 Plate
at 532 nm
Flip-Up Mirror
ND Filter 1 ODReduces output to <0.7 mW (Class 2)
Filter 1 ODReduces output to <0.5 mW (Class 2)
Figure 2. Schematic for SLAC’s laser alignment practical training class.
312LaserSafety_Layout 1 2/22/12 3:09 PM Page 48
800-nm beam: An 800-nm beam is out-side the normal visible range but stilldimly visible when viewed on a whitecard if it has high enough power. Somelaser personnel unwisely take advantageof this to perform certain tasks while notwearing LEP. They can become compla-cent about the associated hazard becausethe perceived hazard is less than whatone observes with a low-power visiblealignment laser or laser pointer. The dif-fuse reflection hazard at 0.5-m viewingdistance from a white card is typically104 to 105 times less than the direct beamhazard. And even if the diffuse reflectionhazard is below physiological damagethresholds, unintended stray beams at0.1–1 percent of the direct beam are veryhazardous. If LEP is removed for a task,one often is giving up OD5 (attenuationof 105) or more in protection – a hugeamount of safety to give up. If thesebeams were operating instead at 532 nmin the green, they likely would be intimi-dating enough that laser operators wouldwant to wear the required LEP.
• Hazards from polarizing beamsplitters:Laser beams should always – to the ex-tent practical – be kept in the horizontalplane below eye level, with any associ-ated stray beams (e.g., partial transmis-sion in a dielectric mirror) also blockedand kept in the horizontal plane. It issometimes necessary, however, to use
optics that generate out-of-plane beams,including periscopes, polarizing beam-splitters and diffraction gratings. Extracaution and special training are neededto use these optics safely, with goodawareness of common mistakes madeand how to avoid them.
Meet the author Dr. Michael B. Woods is the laser safety officerat SLAC National Accelerator Laboratory,Menlo Park, Calif.; email: [email protected]. This work is supported by the US Department of Energy under contract numberDE-AC02-76SF00515.
References1. M. Woods (2011). Lessons learned from a
recent laser accident. Intl Laser Safety Conf,SLAC-PUB-14346, http://slac.stanford.edu/pubs/slacpubs/14250/slac-pub-14346.pdf
2. M. Woods and S. Edstrom (2011). Lasersafety: a laser alignment practical trainingcourse. Intl Laser Safety Conf, SLAC-PUB-14345, http://slac.stanford.edu/pubs/slacpubs/14250/slac-pub-14345.pdf
Photonics Spectra March 2012
LASERS IN USE
Michael B. WoodsSLAC
Figure 3. SLAC’s laser alignment practical training course setup.
312LaserSafety_Layout 1 2/22/12 3:09 PM Page 49
Photonics Spectra March 201250
Images acquired at 8.93, 9.37 and 9.81 µm with a TASI-600 hyperspectral system help geologistsmap mineral resources over theCuprite Hills in Nevada. Courtesy of ITRES Research Ltd.
312RemoteSensing_Layout 1 2/22/12 4:37 PM Page 50
51Photonics Spectra March 2012
Multispectral ImagingExplores Harsh Environments
BY LYNN SAVAGEFEATURES EDITOR Identifying the fluctuating state of the en-
vironment is a massive undertaking thatrequires thousands of people to trek to
some of the most desolate corners of theglobe. From arid deserts to forsaken lakesand rivers and everywhere in between, thesearch is on for plants, minerals, water,soil and other materials that reveal thehealth of the ecosystem. These samples,once collected, are then chemically ana-lyzed with hopes of determining not onlytheir native states, but also whatever out-side influences are taking a toll on them.
To find out, for example, how an oilspill may influence the aquatic life in ariver delta or how acidic runoff from agold mine might seep into wells that pro-vide water to a town, collecting soil andwater samples from a handful of sites nolonger is satisfactory. Instead, environ-mental investigators increasingly collectspectrographic information from sensorsimplanted in the belly of an airplane, ahelicopter or even a low-orbiting satellite.
As with any lab-based spectrometer, re-mote multispectral and hyperspectral im-
agers collect and analyze the spectral in-formation from the target under its gaze.Spectral differences not only help differen-tiate between the leafy canopy of a denseforest and the algae in a nearby lake, butalso between species of trees and otherplants within that same forest.
How much data these specialized sen-sors can collect depends on the wave-length range to which they are sensitive.The difference between multispectral andhyperspectral imagers is nuanced, but,generally, both provide data from a multi-tude of wavelengths. Multispectral im-agers, however, acquire imaging data only(and from discrete wavelengths to boot),while hyperspectral devices provide bothimaging data and full spectra at each pixelas well as scanning within a range ofwavelengths. For example, a multispectralimager may acquire an image of an icefloe at 600, 1200 and 3600 nm; a hyper-spectral imager given the same task couldlook at every wavelength between 600 and3600 nm.
“There is 20 years of spectral research
From the ice and snow of Antarctica to the daunting heights of the Andes Mountains or the effluent-choked waters of the Amazon, the world offers plenty of forbidding environments that beg to be investigated spectrally.
Left: Field photograph of the Los Tollos volcanic center near the town of Rodalquilar in Spain, which is an area of extensive hydrothermal alteration. Center: A natural color composite image shows the same site via data derived from the HyMAP airborne hyperspectral imager. Right: More data from the HyMAP imager shows hydrothermal alteration mineralogy of the area. The reddish colors are likely areas with gold mineralization. Red colors indicate intense alteration of the rocks and the presence of alteration minerals such as alunite and kaolinite. Green areas are related to alteration, but at lower temperatures and pressures, and are predominantly associated with the mineral illite. Blue areas are unaltered volcanic and sedimentary rocks. Pixel size of the HyMAP image is 4 � 4 m. Image maps produced by Frank van Ruitenbeek of the University of Twente. Data Credit: DLR of Germany.
“Hyperspectral will be
the next hit after lidar,
and the best news of all
is that those two combined
support each other’s
strengths and weaknesses
wonderfully.” – Petri NygrénSpecim Spectral Imaging Ltd.
312RemoteSensing_Layout 1 2/22/12 4:37 PM Page 51
to tap into, and it means a vast scope ofenvironmental applications for monitoringvarious attributes in soil, water and vege-tation,” said Petri Nygrén of Specim Spec-tral Imaging Ltd. in Oulu, Finland. He isin charge of the company’s AISA airborneimaging systems – hyperspectral systemsthat cover the visible, near-infrared, andshort-wave and long-wave infrared re-gions.
The resolution offered by aircraft-mounted remote sensors varies not onlywith the device type, but also with flightspeed. For example, the broadband imagerTABI-1800 from ITRES Research Ltd. ofCalgary, Alberta, Canada, offers a spatialresolution of about 15 cm at an airplane’s150 to 200 knots, but about 2.5 cm at themore genial rate provided by helicoptertransit.
The great forests of the world have always captured the imaginations of thepopulations that live around them. But ithas been a while since people looked atthem mainly as a source of wood andother resources, or even as a place to visitevery once in a while to “commune withnature.” People still look at forests as a valuable resource, now without evenhaving to cut them down.
52 Photonics Spectra March 2012
Multispectral Imaging
The ITRES Research Ltd. CASI-1500 captures images of cityscapes and other natural environments at 380 to 1050 nm, with a resolution of 25 cm. Courtesy of ITRES.
312RemoteSensing_Layout 1 2/22/12 4:37 PM Page 52
Sensing and imaging technologies for defense, security, industrial applications, and the environmentLocationBaltimore Convention Center
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312_SPIE_DSS_Pg53_Layout 1 2/22/12 5:26 PM Page 53
The world’s forests together compriseone of the most controllable carbon banksavailable. Forests currently cover aboutone-third of the Earth’s land surface, and,according to NASA, as much as 45 per-cent of the carbon stored on land is held inthese forested areas. Carbon released dur-ing wildfires or when trees are felled andconverted into fuel adds to the carbondioxide in the atmosphere, adding to thetrapping of heat in the atmosphere.
Scientists at Woods Hole Research Cen-ter in Falmouth, Mass., and at more than adozen other institutes are delving into theparticular role that trees play in carbonbanking, or sequestration. They want toknow if today’s forests are holding asmuch carbon as they have in the past, and how they might be better maintainedfor future sequestration needs.
Using data from the lidar instrument onthe Ice, Cloud and land Elevation Satellite(ICESat), the Moderate Resolution Imag-ing Spectroradiometer (MODIS), theQuikSCAT scatterometer, and the ShuttleRadar Topography Mission, researchersare mapping where the best carbon storageis taking place. They also are looking atdata that will help preserve the health ofthe forests.
“Forest hygienics studies have the op-portunity to assess the health of forests as
a whole and particularly the spread of par-asites or diseases,” said Specim’s Nygrén.(For information about ICESat-2, the nextgeneration of the technology, read “Pho-tonic Sensors Help Keep Earth Clean,Green” on p. 67.)
Orbiting sensors such as the AdvancedSpaceborne Thermal Emission and Re-flectance Radiometer, which is part ofNASA’s Earth Observing System, are ex-tremely useful to geologists as well as toforesters. Mineralogists and gas/oil spe-cialists use data collected at short-wave in-frared wavelengths and longer to identifysites worthy of exploiting.
Geologists have long used spectroscopictools to analyze rock and soil samplescarefully located and removed to fieldbases or brought home to university labs.
Freek D. van der Meer and his col-leagues at the University of Twente in theNetherlands use both field and remotelygathered spectroscopic measurements tostudy hydrothermal systems – areas ofvolcanic land through which water andother fluids circulate, bringing about min-eralogical changes. This passage of liquidsleaches some minerals out of the rocks,but new minerals are formed and left be-hind as well.
Any remaining patterns of mineraliza-tion provide information about the fluid
pathways through the system as well asthe pressure and temperature conditionsthat have existed in the rocks. Studyingfluid movement, temperature and pressurehelps researchers to understand the under-lying geologic processes and to predictwhere various bodies of specific ores arelikely to occur. Such research also helpsinvestigators understand and predict thegeology of other planets, such as Mars.
Locating ores is not the sole purpose ofremote imagers. Oil and gas engineers usemultispectral or hyperspectral data to iden-tify environmental risks at existing miningsites and oil fields, and soil scientists usethe technology to map properties indica-tive of soil fertility and soil erosion, whichcan aid farmers and forest managers withtheir long-term planning.
Adrift in the AmazonTracing the metals, acids and other
toxic materials that are the by-products ofmining operations is important for the pro-tection of globally and regionally impor-tant river systems. This is particularly truefor the great rivers, such as the Amazon,which wander for hundreds of milesthrough both populated areas and highlyinaccessible ones.
With its many tributaries and adjoininglakes, the Amazon has a wealth of water
54 Photonics Spectra March 2012
Multispectral Imaging
An overhead view of Villacañas, Spain, acquired in the short-wave infrared with the SASI-600 imager. Images in this band provide high-fidelity object classification,plant speciation and other vital data. Courtesy of ITRES.
312RemoteSensing_Layout 1 2/22/12 4:37 PM Page 54
sources, some of them crossing throughgold mines that dot the South Americanhills through which the river system flows.Gathering water samples by hand wouldbe an impossibly tedious task and couldnot supply nearly large enough samplecollections, so Felipe de Lucia Lobo andhis colleagues at Instituto Nacional dePesquisas Espaciais in São José dos Cam-pos, Brazil, looked to the reflections offthe Amazonian waters.
“Because the region is too large, weneed tools that provide information aboutwater quality in a large scale,” Lobo said.
Lobo, who now is pursuing the projectfrom the University of Victoria in BritishColumbia, Canada, compiled reflectancedata from several remote sources, includ-ing NASA’s Hyperion instrument and the
European Space Agency’s MERIS (Medi-um Resolution Imaging Spectrometer).The former provides per-pixel resolutionof 30 m, while the latter provides a resolu-tion of 250 m. Data from these spectrawere tested against those gathered fromfield tests using handheld spectroradi-ometers.
The data from the multispectral imagersproved that the Amazon’s waters containvariable – and detectable from afar – con-centrations of optically active components(OACs). These OACs comprise such ele-ments as phytoplankton pigments, inor-ganic suspended solids, dissolved carbonfrom decayed plants and animals, andwater molecules themselves.
Lobo’s group sorted the OACs into several broad groups that help define the
water sources from which they originated:• Clear waters with low concentrations
of OACS.• “Black” waters rich in dissolved organic
compounds.• Waters with large concentrations of
inorganic suspended solids.• Waters dominated with chlorophyll
from phytoplankton.
For these studies, Lobo said, field re-search using handheld spectroradiometersremains the best way to collect data – for now. He and his colleagues reported,however, that the remotely gathered re-flectance data provided classification accuracy as high as 67 percent.
Lobo’s plan is to continue using remote-sensing and specialized geographical dataanalysis to monitor inland water quality.
“I want to provide key information thatactually supports regional policies in orderto improve water resources managementand quality of life,” he said.
Technological evolutionHyperspectral imaging technology has
matured from the research labs and is rap-idly finding its way into commercial appli-cations, Specim’s Nygrén said. “The mainproblems the hyperspectral industry isnow facing are related to creating an effi-cient work flow with easy-to-use analysistools.”
The number of remote sensor users isgrowing, and these clients are looking forseveral things, according to Daren Tru -
55Photonics Spectra March 2012
Multispectral Imaging
The MuSIC (Multiple Sensor Instrument Controller) system from ITRES Research Ltd. shows data from up to three sensors in a single real-time display. Courtesy of ITRES.
From an image combining hyperspectral and lidar data, vital information about the health of this forest in British Columbia can be gleaned. From this data, researchers determined a list of trees that included species, height, spectra and overall health. Courtesy of Specim Spectral Imaging Ltd.
312RemoteSensing_Layout 1 2/22/12 4:37 PM Page 55
deau of ITRES Research. They want betterperformance, more technical capability,smaller sizes, wider swatch coverage andsimultaneous data collection across a widespectral band, he said. They also wantfaster access to the data once it is col-lected.
As with most technologies, improve-ments in one area may bring about reduc-tions in another, a fact of which manufac-turers of hyperspectral imaging systemsare keenly aware.
“We’ve strived to produce imaging sys-tems that are physically smaller with eachsucceeding generation,” Trudeau said.“Ultimately, though, shrinking the size ofthe system often incurs a performancepenalty, which may be acceptable forsome users.”
Likewise, Trudeau noted, imagers thatcover ever-wider swaths of territory in asingle pass reduce operational costs andallow for higher spatial resolution, buttend to be more expensive.
But there is more to hyperspectral imag-ing than merely spatial resolution, accord-ing to Nygrén. “Real applications with re-peatability require high spectral resolution,spectral stability and sensor sensitivity.Having an instrument with those qualitiesdoes not come without a cost.”
“I am an application person more than a sensor person,” van der Meer said. “Ithink that we would greatly benefit from ahyperspectral mission in space, as it willprovide access to data in any place in theworld rather than being dependent on aircraft campaigns, which are costly andtypically ‘one off’ experiments.”
Having said that, he added, there re-mains the trade-off between spatial resolu-tion, global coverage and repeatability.“We need global coverage for data acces-sibility, we need repeated observations toallow monitoring and, hence, make thelink to studying dynamic processes, andwe need protocols and standards so thatmeasurements are reproducible.”
Because 70 percent of the Earth’s sur-face is covered by oceans, van der Meersaid, there is a lot of sea bottom that likelywill have much great geology left to ex-plore – which will be difficult even withadvanced remote sensors. There are evenareas uncovered by water where nearlyvertical cliffs and overhanging areas likelywill occlude use of remote sensors.
Future improvements in hyperspectralimaging may come from research intonovel sensor materials or from new waysto sift through large amounts of data. Buteven as novel remote sensing applicationscontinue to stack up, ongoing researchwill go only so far.
Improvements will come not only from scientific research, but also from unexpected sources, van der Meer said.“Breakthrough science is rarely planned.”
56 Photonics Spectra March 2012
Multispectral Imaging
Lynn [email protected]
“Breakthrough science is rarely planned.” – Freek van der Meer, University of Twente
312RemoteSensing_Layout 1 2/22/12 4:37 PM Page 56
The latest in photonics for researchers,
engineers, product developers, clinicians
and others in medicine, biotechnology
and life science.
Subscribe at www.Photonics.com/Subscribe
From the publisher ofPhotonics Spectra magazine.
MICROSCOPY
SPECTROSCOPY
IMAGING
OPTICS
LASERS
BRINGING L IGHT TO L IFE SCIENCE
312_BIO House Ad_Pg57_Layout 1 2/22/12 5:27 PM Page 57
Ultrafast Fiber Lasers Enable Unique Materials Research
BY DR. TONY LINCALMAR LASER INC.
The growth of optical fiber technologyis not restricted to the industrial lasermanufacturing sector: The diversityof fiber laser applications goes way
beyond cutting, welding and materialsprocessing applications. The intrinsic ro-bust architecture and low maintenance offiber-based architectures – coupled withexceptional performance parameters suchas ultrashort pulse widths, higher pulse energies, flexible repetition rates, broaderwavelength coverage and phase locking –are extending the capabilities of multiuserlight source facilities to enable innovativeresearch studies.
Over the past several years, fiber lasershave made increasing inroads into themarket and now account for more than 10 percent of the overall nondiode lasersegment. Although most of the marketpenetration has been confined to the in-dustrial manufacturing sector, the advan-tages of fiber lasers in terms of turnkey re-liability, intrinsic stability and predictableoperation in a relatively small footprintappeal to a much wider customer base.
And further market growth is likely,through both new applications and marketshare erosion of conventional lasers. Re-searchers also are embracing ultrafast fiberlaser technology at multiuser facilitiessuch as SLAC National Accelerator Labo-ratory in Stanford and Lawrence BerkeleyNational Laboratory (LBNL) in Berkeley,both in California.
Advances in synchrotron and free-electron lasers (FELs) are providing researchers with access to ever-brighterand -shorter x-ray sources. For manyyears, Stanford Synchrotron RadiationLightsource (SSRL) has provided pulsesof x-rays for investigating the molecular
and crystallographic structure of materials.More recently, the development of a “low-alpha mode” has allowed access to x-ray pulses of 1-ps duration.
Meanwhile, the Linac Coherent LightSource (LCLS) at SLAC is delivering sub-100-fs pulses with ~1012 x-ray photons atwavelengths as short as 0.15 nm. Theseultrafast hard x-ray pulses, with both highspatial and temporal coherence, are en-abling the investigation of new fields ofscience, from 3-D imaging and dynamicalstudies of important biomolecules to char-acterizing transient states of matter.
In a synchrotron or FEL, energy is ex-tracted from an electron beam that passesthrough an undulating magnetic field. Thepath of the electrons is bent back and forthby an array of magnets of alternating po-larity, causing a release of energy in theform of light. In the case of a synchrotron,the radiation is spatially incoherent with
typical pulse durations on the order of 100 ps, whereas FELs emit an intense,spatially coherent output beam with pulsesas short as tens of femtoseconds. To sup-port operation at hard x-ray wavelengths,the electrons must be tightly bunched sothat they interact coherently with the re-leased light (effectively achieving self-am-plified stimulated emission).
Because an FEL has no resonator and isa single-pass device, an extremely brightelectron beam is required to achieve gainsaturation. This is sometimes accom-plished by using a conventional ultrafastlaser source (such as Nd:YLF or Ti:sap-phire) to excite a photocathode in an ac-celerating radio frequency (RF) field toserve as an electron injector. Synchroniza-tion is achieved by locking the ultrafastlaser to a master clock that also is control-ling the Linac.
In addition, for a number of synchro-
Photonics Spectra March 201258
Although ultrafast fiber laser technology is perhaps the catalyst that will finally allow the nascent industrial ultrafast laser market to reach its full potential, researchers also are embracing this technology for cutting-edge science.
Cazadero Oscillator(39.7 MHz)
25 ns
Error Signal
PhotoDiode
Mixer
476 MHzBandpass
12th Harmonic
Synchrotron RF(476 MHz)
Figure 1. Schematic/block diagram of the synchronization scheme.
Ultrafast Fiber Lasers Calmar Feat_Layout 1 2/22/12 3:15 PM Page 58
trons around the world, time-resolvedbeam lines have been developed usingconventional ultrafast sources to enablepump-probe studies. For each of theseconfigurations, however, a major draw-back has been that conventional solid-state ultrafast amplifiers typically con-sume an enormous optical table and require daily maintenance to ensure opti-mum performance.
Professor Aaron Lindenberg of StanfordUniversity overcame this problem atSSRL by using a turnkey ultrafast fiberlaser, the Cazadero from Calmar Laser.Designed for demanding OEM medicaland microelectronics processing applica-tions, the laser’s compact size and simplesetup facilitate convenient installation andrelocation from one experimental beamline to another. Furthermore, its high pulseenergy (up to 20 μJ at <500 fs) and highrepetition rate play to the strengths of theSSRL, enabling time-resolved studies withan excellent signal-to-noise ratio.
In Lindenberg’s initial experiments, theultrafast fiber laser, operating at a repeti-tion rate of 1.28 MHz, has been success-fully phase-locked to the synchrotron 476-MHz RF signal (Figure 1) with a tim-ing jitter of less than 1 ps and used to di-
rectly measure the x-ray pulse duration.Figure 2 shows direct measurements of thesynchrotron pulse in a short-pulse x-raymode. The experiments are carried out bycross-correlating in a barium borate crystalvisible light at 500 nm generated by the
synchrotron with the laser’s phase-locked1030-nm output and detecting the sum fre-quency-mixed signal at 340 nm. The short-est pulses recorded are ~3 ps in duration.
The synchronism of the optical and x-ray pulse enables a unique class of
59Photonics Spectra March 2012
Figure 2. Pulse width of synchrotron from cross-correlation signal.
Figure 3. X-ray goniometer; at center, a sample is illuminated simultaneously by x-rays and second-harmonic light (515 nm) from theCazadero laser system.
Ultrafast Fiber Lasers Calmar Feat_Layout 1 2/22/12 3:15 PM Page 59
pump-probe experiments (Figure 3). Thehigh-energy output pulse of the fiber lasersystem pumps or excites a sample, induc-ing a kind of physical or photochemicaltransformation. The change then is interro-gated at the atomic level by an x-ray pulsefrom the synchrotron. By varying the ar-rival time of the probe pulse, the dynamicsof the process can be followed as an “x-ray movie” of the structural changesoccurring at the atomic level. The ap-proach is being used to gain a better un-derstanding of the excited-state dynamicsof nanocrystalline systems and the way inwhich they differ from their correspondingbulk structures.
In a recent study, Lindenberg’s groupused the laser source to photoexcite a sys-tem of nanocrystalline silver selenide(Ag2Se) and successfully used the x-raysto follow structural transformations occur-ring on ultrafast timescales. Althoughthese initial studies are very encouraging,enhanced detector and sample deliverysystems are now in development to furtherimprove the signal-to-noise levels. Futurestudies are expected to provide insight forthe development of unique catalysts andmore efficient photovoltaic materials.
At LBNL, the Cazadero also has beenchosen to enable the development of alight source called the Next GenerationLight Source (NGLS). In this case, thelaser is again phase-locked but is used toirradiate a photocathode to produce“bunches” of electrons that are acceleratedto high energy in an RF cavity. This sys-tem is being developed as the electron injector for the NGLS.
The NGLS is an FEL producing x-raysinto the kilo-electron-volt energy rangeand will be unique in operating at a mega-hertz repetition rate. Depending on the
choice of photocathode material, the laserwill operate at its fundamental 1030-nmwavelength; its second harmonic, 515 nm;or its fourth harmonic, 257.5 nm.
“The choice of the photocathode lasersystem is critical in the design of a ma-chine devoted to support a user facility,”said Dr. Howard Padmore, experimentalgroup systems leader for the AdvancedLight Source at Lawrence Berkeley. “Wecannot tolerate any human intervention ona daily basis. The Cazadero is a uniquesystem offering reproducible stable opera-tion with a simple on/off switch. In addi-tion, it provides all the key technical spec-ifications such as power, repetition rateand pulse duration for different types ofcathode as well as frequency locking.”
The NGLS high-repetition-rate, high-brightness x-ray source will enable cine-matic imaging of dynamics, determinationof the structure of heterogeneous systemsand development of novel nonlinear x-rayspectroscopies.
Meet the authorDr. Tony Lin is CEO at Calmar Laser Inc. in Sunnyvale, Calif.; email: [email protected].
Ultrafast Fiber Lasers
The synchronism of the
optical and x-ray pulse
enables a unique class
of pump-probe
experiments.
Ultrafast Fiber Lasers Calmar Feat_Layout 1 2/22/12 3:15 PM Page 60
Lasers Change the Shape of the Photovoltaics Industry
BY MARIE FREEBODYCONTRIBUTING EDITOR
L asers may have been made for photo-voltaics (PVs). Many of the materialsused in PVs, such as silicon, metals
and dielectrics, absorb laser light at theright wavelength; short-wave or pulsedlasers enable low optical and thermal penetration depth; fragile materials can be processed without contact; and, oncethe initial investment is made, high pro-duction rates can make laser technologyhighly cost-effective.
But the story doesn’t end there. The potential for further laser development in PV manufacturing is high, with manysolutions currently in testing phase or recently transferred to industry.
A few major headline grabbers of themoment include tailoring of the temporalshape of the laser pulse to obtain fasterand cleaner processes, contact-free laserprinting and the use of short pulses.
In many of the process steps requiredfor novel solar cell architectures, the useof the laser is unavoidable: for instance,for the drilling of holes for metal wrapthrough crystalline solar cells. In others,however, a laser must compete with exist-ing manufacturing technologies. Examplesof such competition include selectiveemitter and edge isolation, both of which could be realized using nonlaser approaches.
Because the architecture of crystallinesolar cells is continuously evolving, lasermanufacturers must follow solar cell man-ufacturer road maps to identify the busi-ness opportunities for laser technologies,sometimes with only a short window of time.
“In fact, some of the well-establishedlaser processes, such as laser edge isola-tion, could be replaced in the future byother, even more complex, approaches,such as one-sided wet etching, which is
more compatible with novel cell architec-tures providing higher cell efficiencies,”said Milan Rosina, technology and marketanalyst at Yole Développement, a marketresearch and strategic consulting companyin Lyon, France.
Although laser technology has beencontinuously improved and successfullyused in several manufacturing steps, theadvantage of using lasers is now more inan incremental cell-efficiency increase orprogressive simplification in some of theprocessing steps than in a considerable improvement.
Contact-free laser printingThat being said, there are a couple of
potential game changers that could chan-nel PV manufacturing into new directions.
Although screen-printing techniques are the mainstream technology for today’ssolar cell metallization, Rosina said theywill become incompatible with thinnerwafers in the near future and will be re-placed by a kind of noncontact technique
more adapted for the handling of fragilewafers.
These techniques, such as plating, ink-jet and contact-free laser printing, stillhave a low throughput compared withscreen printing, but their performances arecontinuously improving. For example, thecontact-free laser transfer printing (LTP)process developed by BASF SE of Lud-wigshafen and Aurentum aurentum Inno-vationstechnologien GmbH of Mainz, bothin Germany, could be particularly adaptedfor high-throughput metallization. LTPwas designed by the Schmid Group ofFreudenstadt, Germany.
“The contact-free laser printing couldbe considered as a hot candidate for a bigchange in the PV industry, because itcould definitely allow using thinner waferswithout increased breakage losses and potentially replace the traditional andproven screen-printing technology,”Rosina said. “Laser solutions may findtheir added value in the near future whenthinner wafers and complex cell architec-
61Photonics Spectra March 2012
Laser technology and photovoltaics manufacturing make naturally happy partners. Lasers lend themselves well to the needs of PV development such as drilling, trenching, ablation, welding and doping.
Electro Scientific Industries Inc. is testing PV technology with several copper indium gallium selenide modulemanufacturers and scribing equipment makers. The PyroFlex 25 flexible pulsed laser can perform the P1scribing process in the difficult case of two-layer molybdenum. Images courtesy of ESI.
312_ Laser Feat PV_Layout 1 2/22/12 3:16 PM Page 61
tures will require noncontact and ‘digital’processing.”
Manufacturers of thin-film solar cellsoften rely on three scribing processes –P1, P2 and P3 – to increase the operatingvoltage of the cells to useful values. Criti-cal to the overall efficiency of the cells,the scribes’ yield in manufacture is an im-portant factor in determining their cost.
In many thin-film manufacturingprocesses, laser scribing has become the preferred method; however, copperindium gallium selenide (CIGS) hasproved unusually difficult to scribe withlasers, and mechanical scribing using adiamond needle is the most commonlyused technique.
Sophisticated ultrafast lasers have beendemonstrated recently as a potential solu-tion, but cost could be a limiting factorhere. Some CIGS manufacturers considerthese lasers too expensive and not suffi-ciently robust for use in a 24/7 manufac-turing environment.
Another new promising approach is the tailoring of the temporal shape of thelaser pulse to obtain faster and cleanerprocesses. This means customizing theshape, height and width of the laser pulse
nanosecond by nanosecond, independentof the repetition rate.
“Such tailored pulse lasers are enablinghigher-quality P2 and P3 scribes on CIGSat lower cost than current mechanical
scribing and could be integrated into solarscribing production systems in 2012,”Rosina said. “The US company ESI [Elec-tro Scientific Industries Inc.] is currentlytesting this technology with several CIGSmodule manufacturers and scribing equip-ment makers.”
ESI is a leading supplier of innovative,laser-based manufacturing solutions forthe microtechnology industry, with head-quarters in Portland, Ore. The companyhas had promising initial results with thelaser technology, which was acquired bypurchasing startup PyroPhotonics LasersInc. of Montreal. The PyroFlex technologyinitially was brought in to assure its sup-ply of the lasers for its memory business;however, ESI now is targeting the poten-tially far larger solar market.
Some advantages of laser scribing arethought to be: higher throughput thancurrent needle scribing processes, elimi-nation of the need to fix a scribing needleonce it has dulled, and the potential forscribes to be spaced closer together, sinceno longer must space be left to allow forchipping.
ESI PyroPhotonics’ senior product manager Marco Guevremont explainedthat the PyroFlex 25 laser series combinesthe benefits of fiber laser technology withESI’s tailored pulse capability, enabling anew generation of laser processing appli-cations that lie beyond the capabilities ofQ-switched and picosecond lasers.
“Available in the infrared or green, thePyroFlex 25 programmable tailored pulsefiber laser platform provides users with
62 Photonics Spectra March 2012
Lasers in PV Manufacturing
312_ Laser Feat PV_Layout 1 2/22/12 3:16 PM Page 62
complete, individual control over the pulseparameters, including temporal width, energy and repetition rate,” he said. “Italso provides fine and detailed controlover precise pulse shape and complexpulse trains.”
Working with the US Department ofEnergy’s National Renewable Energy Lab-oratory and multiple CIGS manufacturers,ESI’s PyroFlex 25 has demonstrated theability to produce clean P2 and P3 scribeswith no melting of the CIGS at the side-walls, leaving the molybdenum layer undamaged.
“This ability to remove material withoutmelting, using pulses in the sub-10-nsrange, is key to maximizing device yield oncomplex materials like CIGS – where pre-serving the crystalline phase is essential to electrical performance,” Guevremont said.
Additionally, the laser also can be usedto perform the P1 scribe in the difficultcase of two-layer molybdenum, whereassome other commercial laser scribeprocesses can scribe only single layers ofthe material.
Short pulses make short work of itAnother laser technology making its
way into PV factories is the short nanosec-ond infrared pulsed fiber laser. This laseris attracting attention for CIGS P2 and P3 scribing, where it can be used in the selenium-boil-off process. This involvesrapidly boiling the selenium using shortlaser pulses at the interface with the underlying molybdenum.
A drawback to this process is that, because many of the coatings used byCIGS vendors are nontransmissive in the
infrared, this works with only a fraction of the CIGS vendors’ materials.
“Outside of this subset, the processingneeds to be done using direct ablationwith a green picosecond laser such as ourTalisker product,” said David C. Clark, aproduct line manager at Coherent Inc.“Unfortunately, the costs of a tool withmultiple picosecond lasers are rather pro-hibitive, and, as such, the direct ablationapproach hasn’t really been accepted intoproduction yet. But we have hopes that itwill at some point.”
Speed, speed and more speedSpeed is the most challenging aspect
that laser manufacturers must overcomebecause throughput and yield are the keyto lower solar cell manufacturing costs,said Yole Développement’s Rosina.
For example, some laser processingsteps, such as selective emitter formations,typically require two lasers to achieve the desired process speed. “To processemitter-wrap-through (EWT) cells, laserdrilling speeds of approximately 10,000holes per second (not available today by industrial lasers) is required. This is hindering the introduction of EWT cellsinto commercial production,” he said.
According to ESI PyroPhotonics’Guevremont, the PyroFlex 25 recentlydemonstrated drilling speeds that meet industry requirements for the implemen-tation of the EWT process with front-side-back-side PV cell manufacturers.
However, to increase laser processingspeed, the requirements on laser pulse energy, accurate beam spot positioning,beam shape, beam energy time profile and reproducibility will become evenmore challenging.
“One of the main hindrances of lasermanufacturing is the fact that the laserbeam is usually performing very locally.But a solar cell is a large-surface elec-tronic device, and, therefore, the surfacetreatments, such as laser texturing of solar wafers or EWT cell processing, remain costly and very time-consumingprocesses,” Rosina said. “On the otherhand, the local (‘digital’) character oflaser processing is required to realizespecific features such as a locally dopedprofile for selective emitters or locallyablated dielectric layers.”
Therefore, a combined approach oftransforming a high-energy, small laserbeam spot into a desired form, such as aline or a series of lines, could prove verypromising.
63Photonics Spectra March 2012
Lasers in PV Manufacturing
Left and above: In the P3 scribing process, transparent conductive oxide/CIGS is ablated, leaving the molybdenum undamaged.
312_ Laser Feat PV_Layout 1 2/22/12 3:16 PM Page 63
Next-Generation CMOS Redefines Trade-Offs for Inspection
Over the past 10 years, CMOS imaging technology has been increasingly adopted by OEMs in
the machine vision industry, althoughprogress has required considerable timeand investment. Integrated circuit designis always a process of optimizing trade-offs between limiters, but innovations indesign and improvements in fabricationtechnology have allowed designers toovercome many traditional practical im-plementation issues and deliver productswith performance that is truly compellingfor machine vision applications.
Future generations of CMOS technol-ogy will continue to enhance the perform-ance of imaging devices. Now users canbenefit from high-resolution, high-speedimaging devices that provide image qual-ity that exceeds application requirements.Future generations of CMOS technologywill defy today’s limits with unprece-dented combinations of imaging device attributes.
Designing the most suitable camera fora specific machine vision application re-quires a delicate balance between theneeds of the machine vision system andthe various attributes of the image sensorand camera.
Trade-OffsThree main attributes define the primary
set of trade-offs for an area imaging de-vice. The first set can be observed in im-aging performance: image quality, maxi-mum number of frames per second andresolution. The second set is in the func-tionality of the camera or sensor, wherecompeting features call for difficult deci-sions. Examples of these secondary trade-off attributes include features such as win-dowing and power consumption. Finally,there are feasibility trade-offs dealing withcost, yield, reliability and other featuresrelated to the manufacturing of the imag-ing device.
Although in the past, image qualitythresholds required the use of interlinetransfer CCD sensors in many applica-tions, improvements in the design of
CMOS sensors have led to better imagequality and opened up new possibilitiesfor much faster inspection systems withthe desired image quality.
Historically, CCD interline transfer wasthe dominant sensor technology for shut-tered imaging. The first generation ofCMOS technology entered the market of-fering only rolling shutter functionality,which precluded its use in most shutteredapplications, despite the opportunity forhigher speed and lower power and cost.Later on, the CMOS global shutter featurewas introduced, solving the rolling shuttershortfall and allowing CMOS to be rele-vant to more users. Recent advances havevastly reduced the noise and improved thesignal-to-noise ratio levels in CMOS.
Now, in high-speed machine vision ap-plications, CMOS meets or exceeds CCDinterline transfer technology in functional-ity, performance and cost.
The latest generations of CMOS imag-ing technology have diminished the trade-off between resolution and speed by usingvery high data throughput, made possibleby very fast, high-bandwidth analog-to-
Photonics Spectra March 201264
In the CMOS imaging device design process,some trade-offs are relatedto the physics of operatingthe device; others are dueto practical non-idealities in the implementation of thedesign. To come up withan optimal CMOS imag-ing device design, all ofthese factors should be considered.
BY BEHNAM RASHIDIAN AND ERIC FOX, TELEDYNE DALSA
Resolution Speed
Image Quality
Figure 1. CMOS image sensor primary trade-off.
Images courtesy of Teledyne Dalsa.
FEATteledyne_Layout 1 2/22/12 4:48 PM Page 64
digital converters. The speed of these de-vices has challenged the boundaries ofavailable data transmission standards suchas Camera Link and has been the primarydriving force behind the new high-band-width Camera Link HS standard.
Advances in pixel structures, such asglobal shutter pixels, have already nar-rowed the gap between speed and imagequality, which in the past was an issue inhigh-speed applications. This technologycurrently is a de facto standard for anyhigh-end CMOS image sensor.
Use of features such as pinned photo-diode technology and optimized implanta-tion techniques reduces the dark currentand number of “hot pixels” as well as thenoise and lag in an image. This has im-proved the pixel signal-to-noise ratio. Alower noise floor means that new imagerscan be used with less illumination at fasterframe rates and still achieve the sameimage signal-to-noise ratio as older,slower, noisier designs.
The benefits of the new CMOS imagingtechnology are not confined only to theimaging sensor. Advances in CMOS cam-era design techniques also have offerednew possibilities in terms of imaging per-formance. For example, real-time embed-ded processing in the camera compensatesfor non-idealities in the sensor, such aspixel response nonuniformity correction.This embedded processing also simplifiesthe vision system by performing process-ing that traditionally was done in a framegrabber, such as in-camera real-time flat-field correction. Windowing capability andthe ability to change camera aspect ratioare other examples of how camera designin conjunction with a CMOS image sensorcan provide additional capabilities to anend user.
Competing factorsWhen it comes to CMOS pixel structure
design, a few fundamental competing fac-tors define the performance of the CMOSimaging sensor. Some of these trade-offsare fundamental and physical, and someare due to non-idealities in the silicon orin the implementation of the device. In thepast, a primary focus of CMOS technol-ogy development was overcoming imageartifacts. The user must pay close attentionto the performance of a CMOS image sen-sor with regard to artifacts arising in ex-treme situations, or related to certain oper-ation and lighting situations. This con-sideration heavily affects a designer’s de-
cision when faced with design trade-offs.A sensor with an excellent combination ofspecifications may prove to be unusable ifit exhibits image artifacts.
Some of the major trade-off parametersare:1. Fill factor: An inverse relationship ex-
ists between the number of transistorsin a given pixel and its fill factor – thepercentage of light-sensitive area in apixel. Fill factor directly affects thesensitivity of a sensor and the signal-to-noise ratio of the captured image.On the other hand, having more tran-sistors in a pixel allows for additionalfeatures that enhance image quality,such as global shutter and correlateddouble sampling.
2. Light acceptance angle: To minimizethe impact of an increased number oftransistors per pixel, most CMOSimage sensors use microlenses to com-pensate for some of the lost real estatein a pixel due to the greater number oftransistors. However, microlenses re-duce the “light acceptance angle” in apixel. Using microlenses somewhatimproves the trade-off between thenumber of transistors in a pixel andimage quality.
3. Pixel charge capacity (Qsat) and maxi-
mum exposure level: Another majordrawback of having more transistors ina pixel is reduced pixel charge capac-ity. A reduction in pixel size (increasedresolution for the same-size sensor)means less space for charge storage,which in turn results in lower pixelcharge capacity. Reduced pixel capac-ity affects the suitability of sensors forsome applications. For example, in themany that require the camera to differ-entiate between shades of gray in abright image, shot noise is the decisivefactor, not the absolute noise floor.Since the signal-to-noise ratio in theshot noise limit scales with the squareroot of the captured photon signal,shot-noise-limited applications requirehigh pixel storage capacity. Higherpixel storage capacities also help tominimize the size and impact of sev-eral types of imager non-idealities,such as blooming and parasitic imageartifacts.
4. Minimum exposure time, and resolu-tion and power: Minimum exposuretime directly defines the maximumpractical speed of the imaging device.A sensor that is not optimally designedcan exhibit image artifacts at low ex-posure times while behaving normally
65Photonics Spectra March 2012
VPR
PR TR
SEL
VDD
RST
Figure 2. Teledyne Dalsa’s 5T global shutter CMOS pixel, introduced in 1999.
Figure 3. Distortion, rolling shutter and global shutter.
FEATteledyne_Layout 1 2/22/12 4:48 PM Page 65
at longer ones. In a CMOS sensor design, the minimum exposure time isdetermined by the signal propagationspeed within the sensor. Voltage stabi-lization could be compromised bysuboptimal signal routing schemes.This issue becomes more evident asthe sensor resolution increases. On the other hand, an ability to clock asensor fast enough to capture a reallyshort exposure time will also lead tolarger exposure control feed-throughartifacts as well as higher power con-sumption.
5. Minimum achievable noise level: Theminimum achievable noise level in apixel is important in light-starved ap-plications. Complex pixel circuitryand an increased number of stagescan negatively affect the noise floorof a sensor. Essential techniques,such as correlated double sampling (a must-have feature to achieveequivalent or better noise figures asin CCD interline transfer devices),requires extra memory in the pixelarchitecture. This additional circuitryleaves less real estate in the pixel for light collection and signal storage, therefore limiting optical efficiency and maximum signal hand-ling capacity. There are a few schools of thoughton how best to implement correlateddouble sampling in CMOS global shut-ter pixels. In general, “charge domain”techniques are superior to “voltage domain” techniques, but the former aremore susceptible to shutter leakage.
6. Shutter leakage: When a CMOS pixelis read out, the charges from the light-sensitive area of the pixel are trans-
ferred to a storage area for subsequentcharge to voltage conversion and datatransfer. Because the storage area cannot be perfectly isolated from theimaging area of the pixel, unwantedsignal may be collected in the storagenode, creating parasitic image arti-facts. To reduce this charge spillage,the charge can be immediately con-verted into voltage and sampled. Thistechnique, also known as voltage do-main global shutter, requires extra ca-pacitors. However, the downsides of this technique are increased noisefloor level relative to charge domaincorrelated double sampling and a negative impact on almost all of thepreviously mentioned performance parameters.
An alternative approach to the voltagedomain global shutter structure is acharge domain structure, where the trans-fer of the image into a shielded area takesplace in the charge domain. This vastlyreduces the complexity of the pixel butrequires optimized implementation of thecomponents within a pixel. To achieve abetter trade-off scheme between globalshutter and other performance parameters,CMOS fabrication process challengesmust be met and overcome. Essentially,with this method, a reduced number ofhigh-quality elements in the pixel achievethe same result as a more complex pixelcircuitry.
Meet the authorBehnam Rashidian is senior product manager atTeledyne Dalsa in Waterloo, Ontario, Canada;email: [email protected] Fox is technical director for CMOS ICs;email: [email protected].
66 Photonics Spectra March 2012
CMOS for Inspection
SEL
VDD
RST
TX
Frame Memory/Sense Node
Figure 4. Voltage domain global shutter architecture.
FEATteledyne_Layout 1 2/22/12 4:48 PM Page 66
Photonic SensorsHelp Keep Earth Clean,GREEN
BY DR. RADU BARSAN, RIO INC.
Photonic sensors play a major rolein a sustainable future and, in par-ticular, in a variety of applicationsin the generation, distribution andconservation of energy, as well as
in the mitigation of the effects of energyproduction and consumption on the environment.
Electricity generation from wind en-ergy is rapidly growing in the US andworldwide, and could provide at least 20 percent of the nation’s electricity by2030. This trend is driving the need forlarger multimegawatt turbines, for on-shore and offshore utility-scale operation,with rotor diameters well exceeding 100to 120 m. As wind turbines increase insize and capital cost, there is a growingneed to incorporate early-warning windshear measurements and turbine struc-tural health monitoring to optimize thedesign, operation and maintenance of the wind turbine – and to protect it with a high level of confidence against danger-ous wind gusts. At the same time, thehigh levels of investment required for thedevelopment of new wind farm projectsdrive the need for improved site assess-ments of the wind resources, over longerperiods of time, to improve the confi-dence level in the returns on investment.
Because of their immunity to electro-magnetic interference, lightning and elec-trical noise, optical fiber sensors have beensteadily gaining in popularity among windturbine manufacturers as a practical, reli-able and cost-effective online structuralsafety and fatigue monitoring tool inte-grated with the condition-based monitoringsystem of wind turbines. Fiber Bragg grat-ing (FBG) strain sensor arrays – either sur-face-mounted or embedded – can monitorthe mechanical behavior of rotor blades in different types of wind turbines. The results can be used during the design andqualification stages to corroborate the
67Photonics Spectra March 2012
Spectroscopic, fiber optic sensing, and light detection and ranging (lidar) technologies increasingly are being employedin the wind and geothermal energy sectors; in making fossil fuel exploration, extraction and distribution as well as fossil-fuel-based energy generation cleaner, safer and more efficient; and in monitoring greenhouse emissions and pollution and theireffects on the planet.
Figure1. Commerciallidar wind-measure-ment systems areamong the many toolsused to keep an eye on the environment.Courtesy of Zephir Ltd.
312EnergyApplications_Rio_Layout 1 2/22/12 4:17 PM Page 67
measured strain values against design models. In service, premounted FBG sen-sors help monitor online the condition ofthe blades while rotating or stationary, and under various wind conditions.
Lidar technology has been used for along time in atmospheric research. Re-cently, it has been having a growing impacton the wind energy sector because, unlikemechanical anemometers, it can measurethe speed of wind remotely. Laser radiationscatters from atmospheric particles (aero-sols, dust, pollen, water droplets) and isDoppler-shifted by the wind. Measuring theDoppler shift can provide accurate speedmeasurements at distances ranging fromtens or hundreds of meters to kilometers.By scanning the laser beam or using sev-eral telescopes at different angles, the windspeed vector components also can be de-rived in real time. Ground-based lidar,which complements wind flow modelingdata, first penetrated the site assessmentmarket as a valuable replacement for mete-orological towers equipped with cupanemometers. Powered by reliable infrared
lasers with a narrow linewidth, wind lidaroperates nonstop over extended periods oftime (months and years), taking and trans-mitting vast amounts of wind speed datafrom multiple points on a prospective siteover many seasons, atmospheric conditionsand altitudes (Figure 1).
Narrow-linewidth semiconductor lasershave become lower-cost, smaller and,most importantly, more stable and reliable.They can now operate maintenance-freeon the nacelle for long periods of time.With the aid of these developments, tur-bine-mounted lidar instruments increas-ingly are being deployed to measure themagnitude and direction of the wind speedat hub height upstream of the turbine (typ-ically 200 m). The supervisory control anddata acquisition, or SCADA, systems ofturbines equipped with wind lidar can now “see” the wind before it reaches theblades. The systems can take appropriateyaw and pitch control actions to eitherprotect the blades from excessive gusts ormaximize the efficiency of convertingwind speed into generated power. This
results in increased component lifetimes,increased turbine availability, and lower-operating and maintenance costs permegawatt of generated power.
Using lasers to monitor the environment
Thanks to their ability to remotely deter-mine the speed and direction of air particlesor molecules, atmospheric lidar systems arean instrument of choice for diverse environ-mental monitoring activities ranging frompredicting the trajectory of volcanic ashplumes after a major eruption, to measuringglobal tropospheric wind fronts to help inweather forecasting (Figure 2).
The extraordinary ranging accuraciesthat can be achieved with ultranarrow-linewidth lasers enable powerful space-based applications for environmental research and monitoring. For example,NASA’s GRACE (Gravity Recovery andClimate Experiment) mission maps theEarth’s gravity field by making accuratemeasurements of the distance betweentwo satellites, using GPS and a precise
68 Photonics Spectra March 2012
Environmental Monitoring
Figure 3. Above: Satellites fly in formation in the GRACE mission. Right: The ICESat-2 satellite uses a laser beam split to illuminate six spots on the ground. Courtesy of NASA.
Figure 2. This direct-detection fringe imagingDoppler wind lidar system is located near the summit of Mauna Loa in Hawaii. Courtesy of Michigan Aerospace.
312EnergyApplications_Rio_Layout 1 2/22/12 4:17 PM Page 68
ranging system (Figure 3a). The gravityvariations that GRACE studies includechanges due to surface and deep currentsin the ocean; runoff and groundwater stor-age on land masses; exchanges betweenice sheets or glaciers and the oceans; andvariations of mass within the Earth. Theresults from GRACE contribute to globalclimate change studies. The GRACE-FO(GRACE-Follow-On) mission, plannedfor launch in 2016, will provide an ul-tralow-noise, frequency-stabilized laserinterferometric ranging capability to thesatellites. The GRACE-FO laser rangingwill measure the distance variations be-tween the spacecraft to the level of 1 nm,allowing a more precise determination ofthe Earth’s gravity field.
Another application, ICESat-2 (Ice,Cloud and land Elevation Satellite-2), isthe second generation of the orbiting laseraltimeter ICESat and is also scheduled forlaunch in early 2016. Its scientific objec-tives are the following: quantifying polarice-sheet contributions to current and re-cent sea-level change and the linkages toclimate conditions; quantifying regionalsignatures of ice-sheet changes to assessmechanisms driving those changes and toimprove predictive ice-sheet models; esti-mating sea ice thickness to examine ice/ocean/atmosphere exchanges of energy,mass and moisture; and measuring vegeta-tion canopy height as a basis for estimat-ing large-scale biomass and biomasschange. ICESat-2’s ATLAS (AdvancedTopographic Laser Altimeter System) in-strument is a multibeam laser altimeterthat uses time of flight to map out thetopology of the Earth (Figure 3b).
Oil and gas exploration and production
Over the past decade, optical fiber sen-sors have gained widespread acceptancewithin the oil and gas industry due to theirreliability, flexibility and low operatingcosts, as well as the benefits brought bytheir multipoint and distributed sensing ca-pabilities. Initial applications have focusedon downhole, single-point bottom-welltemperature and pressure sensing, as wellas distributed temperature and strain reser-voir sensing. More recently, extensive in-terest has been shown in the developmentand commercialization of fiber optic seis-mic and acoustic sensing arrays – land andunderwater – for oil and gas exploration,pipeline surveillance, geophysical moni-toring, reservoir monitoring and manage-ment, geothermal monitoring, and struc-tural monitoring of offshore platforms andoil tankers. Photonic sensors contribute directly to making hydrocarbon explo-ration and production cleaner by helpingavoid spills, reducing the number of re-quired drillings per oil field, and makingoil and gas transportation and distributionsafer and less polluting.
Initially, fiber optic sensing (FOS) wasintroduced in the oil and gas industry asa replacement for legacy electronic tem-perature and pressure gauges, as well asa tool to monitor nonconventional reser-voirs and enhanced recovery in wellsthrough distributed temperature sensingusing either FBGs or Raman backscatter-ing techniques.
FOS technology, having undergone the incubation period required to proveits field-worthiness, is now ready to be
widely deployed in more advanced appli-cations such as pipeline monitoring,leakage detection, high-temperature geothermal wells, intelligent completionsand flow assurance – among others. Thedevelopment of reliable commercial ul-tralow-noise semiconductor lasers thatcan operate maintenance-free from desertto arctic conditions has enabled dynamicacoustic sensing based on coherentRayleigh backscattering technology. Distributed temperature and strain sens-ing, on the other hand, is being ad-dressed with Brillouin optical time-domain reflectometry or Brillouin opticaltime-domain analysis techniques. Dis-tributed acoustic sensing (DAS) enables detection, discrimination and location of acoustic events on an opticalfiber over tens of kilometers.
Using a combination of the measure-ment of backscattered light and advancedsignal processing, the DAS interrogatorsegregates the fiber into an array of thou-sands of individual “microphones.” Applications of DAS are common inpipeline monitoring, intrusion detection,hydraulic fracturing of tight sand andshale gas reservoirs, and passive or active seismic reservoir monitoring (Figure 4).
Seismic permanent offshore oil reservoirmonitoring is an important and growing application of interferometric FOS technol-ogy, with significant contributions to theupstream oil and gas industry (Figure 5). The seismic data is used for monitoring
69Photonics Spectra March 2012
Environmental Monitoring
Figure 4. Fiber optic sensing systems: Left: A commercial distributed acoustic sensing monitoringsystem in operation. Courtesy of QinetiQ. Above: Adistributed temperature sensing data acquisition unitinstalled in a thermal recovery field in the MiddleEast. Courtesy of Qorex.
312EnergyApplications_Rio_Layout 1 2/22/12 4:17 PM Page 69
and mapping fluid movements and pressurechanges in oil and gas reservoirs, and foridentifying bypassed compartments, moni-toring flood fronts, planning infill drillinglocations, and monitoring fracturing andstimulation operations – all of which con-tribute to greener utilization of assets.
Processes, emissions across energy sectors
In the conventional energy sector, opti-cal and photonics-based gas sensors andsensing techniques are effective, practicaltools for the detection, assessment and localization of fugitive gas emissions andleaks – such as hydrocarbons and sulfurhexafluoride (SF6) – in chemical plants,refineries, power plants and gas pipe-lines. The technology also plays an im-portant role in detecting and quantifyinggas emissions, volatile organic com-pounds and pollutants – from hydrogenleak alarms for fuel cells and hydrogenstations, to moisture in natural gas lines;it is also used for monitoring combustionefficiency and emissions in fossil plants.Detection systems are based on tech-
niques such as Fourier transform infrared,Raman spectroscopy, cavity ring-downspectroscopy, differential optical absorp-tion spectroscopy, photoacoustic spec-troscopy and tunable laser absorptionspectroscopy.
Fugitive emissions in refineries resultwhen hydrocarbon vapors leak from pro -cess equipment such as valves, flanges,pumps, compressors and other equipment,and from the evaporation of hydrocarbonspills in open areas. The total quantity offugitive volatile organic compound emis-sions in a typical refinery, with a capacityof 330,000 barrels per day, is estimated at45,000 pounds per day. Fugitive emissionsare typically invisible and oftentimes poi-sonous or flammable. They are also com-mon in the electric power industry. Sulfurhexafluoride is an effective electrical insu-lating gas frequently used in high-voltagegas-insulated switchgear, transmissionlines and breakers. However, SF6 has anextremely high impact on the greenhouse
70 Photonics Spectra March 2012
Environmental Monitoring
Figure 5. A fiber optic seabed seismic sensingsystem. Courtesy of Stingray Geophysical.
effect – more than 23,000 times more severe than an equivalent amount of CO2 – and has a lifetime of 3200 years.SF6 can be emitted from leaking substa-tion equipment, or can be released duringservicing and refilling operations.
A significant portion of greenhousegases are produced by the energy sector,with the largest pollutant contributor beingCO2 from coal-fired power plants. This isprecisely another application where pho-tonic sensors – tunable laser absorptionspectroscopy gas monitoring systems – aremaking an impact by performing in situ,real-time measurements of O2, CO, CO2and water vapor in two dimensions acrossthe boiler flame zone to help improve thecombustion efficiency.
Meet the authorDr. Radu Barsan is president and CEO of RIO Inc. of Santa Clara, Calif.; email:[email protected].
312EnergyApplications_Rio_Layout 1 2/22/12 4:17 PM Page 70
Prism Awards Celebrate Photonics Innovations
Winners of 2011 Prism Awards represented an intriguing mix of European and US-based small companies and established businesses. This year’s winners include a 60-laser system for inspecting train rails at high speed, a dual-lasersource for eliminating fluorescence effects in Raman spectroscopy, and a breakthrough in miniaturizationthat enables speckle reduction in laser-based picoprojectors.
The international competition, co-sponsored by Photonics Media and SPIE, honored the productsintroduced in the past year that challenge conven-tional ideas, solve problems and improve lifethrough the generation and harnessing of light. Over the past four years, the awards have grown tobecome the premier recognition of innovation andnew-product development in the photonics industry.(For a complete list of finalists, see the January2012 issue of Photonics Spectra.)
71Photonics Spectra March 2012
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LIFE SCIENCES AND BIOPHOTONICS
89 NorthHeliophor
The Heliophor is a pumped-phos-phor light engine for quantitativefluorescence microscopy, allow-ing high-speed, live-cell imagingwithout the need for additionalequipment such as shutters andcontrollers. It provides a new alternative to arc lamps, metalhalides and LED light sources, enabling production of awider range of output wavelengths, all matched to commonfluorescent proteins and dyes. The high-speed switching af-forded by the pump source allows the light source to serve asits own shutter, while the internal feedback system maintainsultrastable output power.
“I’m standing on the shoulders of giants.” Dr. JohannesKoeth, CEO, Nanoplus
BY MELINDA ROSE, SENIOR EDITOR
312Prism_Layout 1 2/22/12 4:50 PM Page 71
OTHER LIGHT SOURCES
OEwavesUltranarrow Linewidth Laser
This narrow linewidth laser source is based on theself-injection locking of a semiconductor laser diodeto a proprietary optical whispering gallery mode microresonator. It achieves robust supernarrow instan-taneous spectral linewidth of less than 300 Hz in asmall 14-pin butterfly package. The wide range of optical transparency of the resonator host material allows narrowing the linewidth of a laser at any wavelength – UV to far-IR – making this capabilityavailable in ranges not previously accessible with conventional techniques. These features make the laser suitable for applications in a variety of sensingand communications applications, including harsh environments, as required by many optical-based sensors.
DETECTORS, SENSING, IMAGING AND CAMERAS
MermecT-Sight 5000
This system integrates clear-ance gauge measurement withtunnel wall inspection, sharingthe same laser illuminating
source to inspect and analyze tunnels and clearance profiles on railways and capturing image data of bridges, underpasses,poles, walls, tree branches and other obstacles that may hinderthe safe transport of rail passengers and cargo. The system canbe mounted to the front of a high-speed train, replacing visualinspections that must be performed slowly and during off-peaktraffic hours. The T-Sight 5000 allows inspections to be per -formed in real time at speeds greater than 300 km/h.
72 Photonics Spectra March 2012
When our company was founded 10 years ago, “a funny joke was putting ‘femtosecond’ and ‘industriallasers’ in the same sentence.” – Dr. Eric Mottay, President and CEO, Amplitude Systèmes
SCIENTIFIC LASERS
PD-LD Inc.LabSource VBG-Stabilized DualLaser Source
This dual-laser source is used in shifted excitationRaman difference spectroscopy (SERDS), the pre-ferred method for the elimination of fluorescence ef-fects in Raman spectroscopy. It allows taking Ramanspectra at two very stable and precisely spaced laserwavelengths and replaces more costly tunable lasersfor subtracting the fluorescence contribution from theRaman signal. Volume Bragg grating (VBG)-stabilizedlaser diodes operate with external feedback from aVBG element. The grating spacing of the VBG deter-mines the wavelength reflected back into the lasercavity and, thus, the emission wavelength of the laser.VBG-stabilized laser diodes have a narrow linewidthand a precisely controlled center wavelength and areconsiderably smaller, cheaper and simpler to operatethan the tunable lasers previously used in SERDS applications.
DEFENSE AND SECURITY
Physical Optics Corp. (POC)Mobile ELISA-Based Pathogen
Detection (MEPAD)
The Mobile ELISA is a biohazard detection system with a highly sensitive portable fluorimeter and automated processingfor disposable microfluidic chips. It provides responders andpoint-of-care specialists with a cost-efficient and automatedELISA-based process for field use and identification of concen-trations below 100 ng/ml. The fluorescence detection subsystemis composed of a 635-nm diode laser, an avalanche photodiodethat measures fluorescence, and three filtering mirrors.
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73Photonics Spectra March 2012
Melinda A. [email protected]
Thanks to the award presenters at Photonics West:Timothy Day, Daylight Solutions; Mary Lou Jepsen,Pixel Qi; Wellington Chadehumbe, Triumph VentureCapital; Michael Lebby, Translucent Inc.; Laura Smoliar, Peppertree Engineering; Robert Huang, Wavelength Technology Pte Ltd.; Michael J. Cumbo,Idex Optics & Photonics; Rob Randelman, Halma; and Larry Marshall, Southern Cross Venture Partners.
“We are a microphotonics company, so winning a prize for lasers is particularly satisfying” – Dr. LuteMaleki, President and CEO, OEwaves
INDUSTRIAL LASERS
Amplitude SystèmesSatsuma HE
This high-power ultrafast fiber laser combinescharacteristics that are usually mutually exclu-
sive: a pulse energy greater than 20 μJ, an average power greater than 10 W, and an air-cooled housing that measures less than 13 � 30 in. Applications for such ultrafast lasers are rapidly growing and include eyesurgery, medical device manufacturing and semiconductor processing.
OPTICS AND OPTICALCOMPONENTS
OptotuneAGLaser Speckle Reducer
Speckle contrast inlaser illumination
is a major roadblock to the laser’s becomingthe “focus free” standard for projection lightsources. Although a traditional approach is to use rotating diffusers, which destroy thetemporal and spatial coherence of the laserand smear the speckle pattern, the LaserSpeckle Reducer uses electroactive polymers(EAPs, also known as artificial muscles) to oscillate a diffuser, enabling speckle reductionin laser-based pico projectors. The diffuser ismounted on an elastic membrane and movedback and forth using EAPs, resulting in a planar circular oscillation of the diffuser with lateral deflections of 100 to 500 μm at frequencies of several hundred hertz.
TEST, MEASUREMENT, METROLOGY
WITec GmbHTrue Surface Microscopy
True Surface Microscopy is an imaging technique that followsthe surface topography with high precision so that even rough or inclined samples always stay in focus while performing confocal (Raman) imaging. With this new imaging mode, samples that previously required extensive preparation to obtain a certain surface flatness now can be effortlessly and automatically characterized as they are.
GREEN PHOTONICS/SUSTAINABLE ENERGY
nanoplusDFB Laser at 3 μm
These DFB (distributed feedback) laser diodesperform at the previously unattainable wave-
length range between 2.9 and 3.4 μm for tunable diode laser spectroscopyapplications, an important technique for gas detection. Reaching that spec-tral range was made possible, in part, by the recent commercial availabilityof application-grade laser sources in that region for sensor applications.
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Imaging Components & Systems
“The Leader in Optical Filter Solutions” Confocal ImagingIridian’s dichroic filters exhibit excellent isolation that reduces background levels from excitation wavelengths. Our filters use hard dielectric coatings,which greatly improve the transmission levels compared with traditional filters. This results in brighter imaging, shorter exposure times, better image quality and a reduced rate of bleaching. Multiwavelength dichroic filters also are available.
(613) [email protected]
www.iridian.ca
Camera Link EquipmentWe offer a broad line of Camera Link supporting devices
• Video Splitters• Repeaters• Multiplexers• Adapters• Camera Simulators• Breakout Box• Custom Engineering• OEM Solutions
(508) [email protected]
Vacuum Valves ManufacturingVAT is the worldwide leader in vacuum valves manufacturing and technology.
VAT products include: angle valves, gate valves, transfer valves, controlvalves, throttle valves, isolation valves, pendulum valves and valves designedfor custom applications. More than 1000 standard products are listed in our catalog.
VAT valve applications include: Semiconductor Manufacturing, PV, Thin-FilmTechnology, Synchrotrons, High-Energy Physics, Fusion Research, Metallurgyand many more.
(781) [email protected]
www.vatvalve.com
New iXon Ultra EMCCD CameraThe iXon Ultra platform takes the popular back-illuminated 512 � 512-frame transfer sensor and overclocks readout to 17 MHz, pushing speed performance to 56 fps (>60% faster), while maintaining quantitative stability throughout. This speed boost facilitates a new level of temporal resolution to be attained, ideal for speed-challenged low-light applications such as superresolution microscopy, single-molecule tracking,ion signaling, cell motility, single-photon counting, lucky astronomy and adaptive optics.
+44 28 9023 [email protected]
See more new products at Photonics.comIt’s easy to find the latest products on our website – Photonics.com. Just click on the menu marked PRODUCTS on the navigation bar (under the logo) to find new products almost every day.
When people ask, “What’s new?” tell them to go to: “Photonics.com/Products.”
(413) 499-0514photonics.com
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75Photonics Spectra March 2012
Imaging Components & Systems
Highest-Resolution SWIR Line-Scan CameraXenics’ Lynx cameras and detectors, covering the SWIR range, are perfectlysuited for remote sensing. The technology development has been supportedby ESA’s General Size and Technology Program:
• Smallest InGaAs detector with 12.5-µm pixel pitch• Highest resolution up to 1 � 2048 pixels• High line rate of 10 kHz up to 40 kHz (1024-pixel version)• Low noise and high dynamic range
+32 16 38 99 [email protected]
New Hybrid Glass Light-Shaping DiffusersHybrid Glass diffusers offer high transmission (up to 92%) from 350 nm to the visible light range. They can withstand temperatures of 150 °C and are available in sizes up to 20 � 20 in. on optical glass or fused silica. They also are available in many circular and elliptical light-shaping angles and can be made with AR coating on one or both sides.
(310) [email protected]
Microdisplays for Structured LightForth Dimension Displays’ high-resolution reflective microdisplays are usedglobally for structured light projection in 3-D optical metrology. The high fill factor (>96%) and linear gray-scale display technology, coupled with theflexibility of the 3DM driver interface, make this the perfect choice for 3-D metrology systems builders. The application-specific driver interface, with its small size, configurable timing, synchronization and I/O ports, hasbeen designed for easy integration into structured light projection systems.So if you want a fast, precise, accurate and cost-effective solution for your AOI, SPI or 3-D inspection system, contact our experts now.
[email protected]+44 1383 827 950www.forthdd.com
iChrome MLE – Multi Laser Engine for Multicolor ApplicationsThe iChrome MLE is a complete solution for demanding multicolor applica-tions in biophotonics. It comprises up to four diode lasers or, alternatively, up to three diodes and one DPSS laser fully integrated into one compact box. The individual lasers are efficiently combined, yielding highest power levels, and are delivered via one SM/PM fiber. TOPTICA’s ingenious COOLAC
technology ensures a Constant Optical Output Level due to push-button auto-recalibration, ensuring exceptional long-term power stability. The microprocessor-controlled system enables flexible OEM integration in instruments such as microscopes or flow cytometers. High-speed analog (1 MHz) and digital modulation (20 MHz) allow fast switching of laser wavelength and intensity.
[email protected](585) 657-6663
ww.toptica.com
Recirculating CoolersJULABO’s F250 EcoChiller and FL300 recirculating cooler provide cooling capacities of 250 and 300 W. The units feature easy operation and high-qualitycomponents for years of trouble-free operation. Contact JULABO today tochoose the unit for your optics, detector and photonics applications.
(800) [email protected]
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� DPSS LasersThe Archimed series diode-pumped solid-state(DPSS) lasers manufactured by RPMC Lasers Inc.offers 45 to 150 mJ of pulse energy at 1064nm, with pulse widths from 9 to 12 ns and rep-etition rates of up to 50 Hz. The compact air-cooled devices also are available with second-,third- and fourth-harmonic-generation options.They can be equipped with an optical paramet-ric oscillator to generate the eye-safe wave-length of 1.5 µm, which produces 10 mJ ofpulse energy with pulse widths from 7 to 9 nsand repetition rates of up to 25 Hz. All lasers inthe series have multimode beam profiles and apolarization ratio of 100:1. They are suitable foruse in light detection and ranging, rangefindingand laser-induced breakdown spectroscopy, andare rugged enough for limited field use.RPMC Lasers [email protected]
� Packaging Submounts Remtec Inc. provides packaging options to de-signers of laser diode, LED and photodiode sub-mounts and substrates, offering ceramic sub-mounts (alumina, beryllia, aluminum nitride),metal heat sinks and enhanced plated gold tinmetallization. Based on plated copper-on-thick-film technology, the submounts offer 25- to 75-µm-thick copper metallization from a burr-free ceramic edge. Gold tin plating on ceramicsubmounts can be applied to edge-emitting andvertical external-cavity surface-emitting laserdiodes, and to copper tungsten submounts andlaser bars. Gold, palladium and gold tin platingfinishes enable the use of gold wire bonding,brazing and epoxy die attach soldering materi-als and assembly techniques. Applications in-clude laser welding, cutting and marking sys-tems; medical (blood-oxygen sensors, trans-dermal delivery systems for medications); skinrejuvenation and hair removal; UV curing oflight-sensitive dental materials, industrial inksand adhesives; 3-D digital printing; and cine-matic lighting.Remtec [email protected]
IDEASBRIGHT
Photonics Spectra March 2012
� FireWire-b Digital CamerasPoint Grey Research Inc. has added 2.8-megapixel models to its Grasshopper ExpressIEEE 1394b (FireWire-b) digital camera series.The GX-FW-28S5M-C (monochrome) and28S5C-C (color) are based on the Sony 2⁄3-in.ICX674 CCD, which features 4.54-µm squarepixels and produces 1932 � 1452-pixel-resolu-tion images at 26 fps. Sony’s EXview HAD CCDII technology improves quantum efficiency, re-duces smear and increases sensitivity into thenear-infrared. Other features include a 32-MBframe buffer, a 14-bit analog-to-digital con-verter, and onboard temperature and powersensors. The included FlyCapture software de-velopment kit provides a common control inter-face for all of the company’s cameras underWindows and Linux. The 800-Mb/s FireWire-binterface allows fast image transfer and buildslow-latency, highly deterministic multiple cam-era networks. The cameras are used in biopho-tonics, medical, astronomy, traffic surveillance,factory automation and machine vision appli-cations. Point Grey Research [email protected]
� USB 3.0 Industrial CamerasImaging Development Systems GmbH has unveiled the uEye CP industrial cameras withthree sensors ranging from VGA to 5-mega -pixel. Measuring 29 � 29 � 29 mm, they arehoused in a magnesium casing and incorporatea USB 3.0 interface that is backward-compati-ble. Vision applications include industrial, med-ical and biometrics. The cameras offer trigger,flash and pulse width modulation, and two general-purpose input/outputs that can bechanged into an RS-232 serial interface for trigger or control of peripheral devices. Bright-ness correction is achieved by a 12-bit look-uptable and hardware gamma. A field-program-mable gate array performs color correction andde-bayering with up to 12 bits per channel, andenables RGB or YUV data output. A softwarepackage for Microsoft Windows and Linux in-cludes 32- and 64-bit drivers, demo programsand source code in C��, C# and Visual Basic. Imaging Development Systems GmbH [email protected]
Ultralow-Absorption Coatings Precision Photonics Corp. offers ultralow-absorp-tion thin-film coatings based on ion-beam-sput-tered (IBS) deposition. The antireflection typesproduce losses of �0.5 parts per million (ppm),and the high-reflection coatings exhibit losses of�2 ppm. Photothermal common path interferom-etry combined with proprietary calibration meth-ods results in measurement sensitivity of �0.1ppm for optical materials such as fused silica. Besides verification of in-house IBS coatings, the
company provides measurement services to customers wishing to measure absorption in their owncoatings or substrates. Two-dimensional mapping of surfaces also is available. Precision Photonics [email protected]
Copper Mirrors for CO2 Lasers �REO Inc. offers copper high reflectors for beam-delivery and beam-shaping tasks involving high-power CO2 lasers. The mirrors feature reflectivity of�99.7% at 10.6 µm, surface quality of 40-20 scratch-dig and low scatter surface roughness of �50 Å. Pro-duced from oxygen-free, high-thermal-conductivitycopper, they deliver good optical performance and amaximum laser damage threshold. They can be pro-duced with plano, spherical or cylindrical surfaces insizes from 6 to 150 mm. Through-holes, mountingflanges and other mechanical features can be accom-modated. Either traditional electron beam or ad-vanced plasma source coating technologies are employed to deliver the durability and damage resistance required for a specific application. The optics are handled in a controlled environmentthroughout the manufacturing process, preventing deterioration of the pristine optical surfaces prior to coating, and maximizing thin-film adhesion. REO [email protected]
�
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Fiber Optic Raman ProbeThe BAC200 from B&W Tek Inc. is amicrolensed fiber optic Raman probethat delivers the performance of alarger Raman probe in a diameter<4 mm with enhanced optical col-lection power. Its design providesimmersion and direct contact mea-surements, enabling applicationsand measurements previously notpossible with standard Ramanprobes. The fused silica tip is housedin a stainless steel needle tube, re-sulting in a scratch-resistant, easy-to-clean device. The optical elementsare permanently fixed in alignment,with no possibility of movementcaused by impact or vibrations. Theprobe’s small size, flexibility anddurability make it suitable for analy-sis in biological and biomedical ap-plications with small sample sizes.Scientists performing molecular-levelspectroscopic analysis can perform invivo analyses of specimens withoutcreating apertures any larger than 4 mm. B&W Tek [email protected]
Large Sapphire WindowsCustom-fabricated sapphire windows and lenses that transmit from theUV to the IR and are impervious to most chemicals, water, and fast-mov-ing dirt and sand are available from Meller Optics Inc. The optics can beproduced in sizes up to 10 in. in diameter, depending upon the diameter-to-thickness aspect ratio. Featuring transmission from 270 nm to 4.7 µm,they are clear as glass, second only to diamond in hardness (Moh 9), andcan withstand temperatures up to 1000 °C. Suitable for use as protectivefront-surface optics and as viewports, they provide flatness to �/10 in thevisible and <2-arcsec in./in. parallelism with finishes from 60-40 to 40-20scratch-dig, depending upon size and construction. Applications includeviewing optics in cameras, weapons and refractometers, and machine inspection windows.Meller Optics [email protected]
Lens Cleaning Kit Laser Research Optics, a division of Meller OpticsInc., is offering a profes-sional lens cleaning kit for the field that includeseverything necessary to re-move spatter and blowbackfrom CO2 laser optics. TheLRO Advanced OpticalCleaning Kit was developedto help prevent damage tocoatings, extend lens lifeand improve laser perform-ance. Supplied with step-by-step instructions, the kitincludes 24 cotton balls, 24surgical-grade finger cots,24 lens mats, distilledwater, polishing compound,reagent-grade isopropyl alcohol and acetone, andan air bulb for dust removal. Improving transmission and increasing lasersystem efficiency, the kit is suited for CO2 lasers used in dirty environ-ments. It also is effective for most precision optics, including CaF2, fusedsilica, germanium, sapphire, silicon, ZnSe and ZnS. Laser Research [email protected]
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Enhanced Laser-Driven Light Sources
Energetiq Technology Inc.’s customers can nowchoose between a standard quartz bulb and anozone-free one on the LDLS EQ-99 and EQ-99FC light sources, allowing them to tailor thespectral range to a particular application whilemaintaining high brightness and long lamp life.The standard synthetic quartz bulb produceslight from 170 nm through the visible and intothe infrared. The ozone-free quartz bulb cuts offlight below 250 nm, where ozone is produced.This optimizes the spectrum for applicationswhere operation in the deep-UV is not neces-sary. The ozone-free bulb produces a broad-band spectrum from 250 to 2100 nm, with thesame brightness as that produced by the stan-dard synthetic quartz bulb, and offers the samelong lamp life. Electrodeless in operation, thecompany’s laser-driven technology in the EQ-99and EQ-99FC provides ultralong lamp life anda broad spectral range.Energetiq Technology [email protected]
Sintering System
With the release of the Sinteron 2010, XenonCorp. delivers flexibility for sintering conductivecopper and silver metallic inks, curing thin-filmsubstrates, and for solar and surface modifica-tions. The 19-in. rack-based stand-alone systemallows for digitally programmable pulse widths.Pulse amplitude can be adjusted, and pulsewidth is adjustable from 100 to 2000 µs in increments of 5 µs. Because the pulse profile islinear at maximum amplitude, a relationship of1000 J/ms can be assumed. The system allowsconnection for either spiral or linear lamp hous-ings. Applications include photonic sintering ofconductive inks for printed electronics in dis-
plays, smart cards, radio-frequency identifica-tion and solar applications. The noncontact low-thermal characteristics for this process make itsuitable for web-based printing techniques suchas ink-jet, flexography, gravure and screenprint.Xenon [email protected]
Rack-Mount High-Voltage Power Systems
UltraVolt Inc.’s HV Rack Advanced and HP Ad-vanced high-voltage power systems producepower up to 90 kW. They offer computerizedfront panels, full controls and displays, digitaland analog interfaces, and an SD card memoryfunction for loading preset user voltage/currentcurves. The systems feature advanced measure-ment and data logging, and standard modes forconstant voltage and constant current, and theyprovide source simulation modes such as con-stant resistive, constant power, photovoltaic andautomotive. Features include good line andload regulation, low ripple and low noise. Theycan be used for simulation of solar panels bytesting inverters and capacitor chargers in thelaser industry. HV Rack Advanced systems offeroutput voltages from 0 to 1200 VDC, currentsfrom 0 to 500 A, and output power to 10 kW.HP Advanced offers 0 to 1200 VDC, currentsfrom 0 to 2250 A, and output power to 60 kW. UltraVolt [email protected]
Temperature-Controlled Lasers
Z-Laser Optoelektronik GmbH’s redesigned ZQ family of lasers offers higher power andgood beam and laser line quality for fiber, homogeneous lines, collimated beam and struc-tured light projections. They can be remote-con-trolled, now that they are combined with agraphical user interface for setting power andmonitoring all parameters. The ZQ2 systemsdeliver a boresight accuracy of <3 mrad andoutput up to 7000 mW between 600 and 1100nm. The Z1000Q1-F-808 delivers output of 1 Wat 808 nm and is accurate to 300 µm, FWHM,in 1500-mm focus. The internal design of theZQ1 is laser-coupled with an integrated ther-moelectric cooler that produces good stabilityand minimum boresight error. Both feature inte-grated optics, electronics and active tempera-
ture control in a self-contained enclosure andsupport communication interfaces including RS-232, USB, Ethernet and programmable logiccontroller, each galvanically isolated. Z-Laser Optoelektronik [email protected]
IR Laser Beam Finder Pathfinder Research LLC has released the Cool-Card II handheld infrared beam finder and IRbeam-quality evaluation tool for use with lasersand other IR sources operating from the near-IRto the 10-µm wavelengths and beyond. Capital-izing on actively thermally stabilized liquid crys-tal technology, the device senses and resolvesthe fine spatial character of lasers operatingnear and well beyond 1.7 µm. Based on theoriginal CoolCard, the new version features arechargeable, field-replaceable lithium-ion bat-tery that provides multihour continuous opera-tion and the ability to be recharged in the labor with the supplied 12-VDC auto adapter. Withsensitivity of a few milliwatts and good spatialresolution resulting from built-in sensor temper-ature control, the compact wire-free CoolCard IIrivals IR cameras in many applications, accord-ing to the company. Pathfinder Research [email protected]
Red Laser
Laser Quantum Ltd.’s compact lux red diodelaser delivers up to 1 W at 660 nm. Features include a diffraction-limited TEM00 beam withM2 <1.2, automatic power control, rms noiselevels of 0.6% and power stability of 1%. Thelaser is based on diode-pumped optical technol-ogy. Applications include fluorescence imaging,spectroscopy, DNA sequencing, Raman spec-troscopy and stimulated emission depletionnanoscopy. The hermetically sealed laser offers>40,000 h mean time to failure, full RS-232control, and a permanently aligned and zero-stress cavity. Beam diameter is 0.75 ±0.15 mm,bandwidth is ~30 GHz, beam divergence is<1.5 mrad, pointing stability is 10 µrad/°C, andpolarization ratio is >100:1. Polarization direc-tion is horizontal, coherence length is <1 cm,beam angle is <2 mrad, and operating temper-ature is from 22 to 37 °C. The instrumentweighs 0.7 kg, and warm-up time is <15 min. Laser Quantum [email protected]
QI for AFM System JPK Instruments AG has developed quantitativeimaging (QI) capabilities for its NanoWizard 3atomic force microscope (AFM). With the QIforce curve-based imaging mode, the user cancontrol the tip-sample force at every pixel.There is no need for set point or gain adjust-ment while scanning. Applying proprietary
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ForceWatch technology, QI delivers good resultson soft (hydrogels, biomolecules), sticky (poly-mers, bacteria), and loosely attached (nano-tubes, virus particles in fluid) samples, and onsamples with steep edges (powders, micro-electromechanical systems structures). It is use-ful in biology, polymers and surface science. QIand QI-Advanced modes make the NanoWizardAFM a versatile instrument for high-end re-search and routine use. Measuring a real andcomplete force distance curve at every pixelyields all information about the local tip-sampleinteraction, with high spatial resolution. QI-Advanced software enables quantitative mea-surement of nanoscale material properties such as stiffness, adhesion and dissipation. JPK Instruments [email protected]
16-Channel MPPC Modules
Hamamatsu Photonics UK Ltd. has introducedmultipixel photon counter (MPPC) modules forevaluation of large-area MPPC detectors. The
S11834-3388DF and the C11206-0404FB bothuse a 64-channel MPPC array of 3 � 3-mm dis-crete detectors, resulting in an effective area of576 mm2. The C11206-0404FB also includes ahigh-voltage supply, a temperature control cir-cuit and a dedicated application-specific inte-grated circuit that includes an amplifier and a digital-to-analog converter. The C11206-0808FA uses a 16-channel monolithic MPPCarray with 3 � 3-mm channels, producing aneffective area of 144 mm2 and allowing formaximum position resolution with minimumdead space. All are available with 3600 pixelsper channel and a 50-µm pitch. Each pixel con-tains a quenching resistor so that simultaneousphoton events can be counted separately. Thedevices feature a typical gain value of 7.5 �105 and high photon detection efficiency in theUV and blue regions, with peak sensitivity at400 nm. They are insensitive to magnetic fieldsand are used in time-of-flight positron emissiontomography, flow cytometry and astrophysics.Hamamatsu Photonics UK [email protected]
VBG-Stabilized Benchtop LasersPD-LD Inc. has announced its LabSource seriesbenchtop laser sources. The LS-1 features a single-volume Bragg grating-stabilized lasersource, and the LS-2 offers dual laser sourcesthat enable it to perform dual-wavelength lighttherapy and specialized analytics. Both are cus-tomizable solutions in a variety of wavelengths
and include integrated drive circuitry and soft-ware, making them easily integrated into exist-ing laboratory instruments. They have a user-friendly interface and feature an ergonomicdesign. The LS-2 analyzes and identifies fluores-cent substances that have previously been diffi-cult or impossible to identify or analyze via tra-ditional Raman spectroscopy, as well as organicand biological samples. The dual-source tech-nique is known as shifted-excitation Raman dif-ferential spectroscopy. The turnkey lasers arewell suited for customers who wish to operate a complete laser solution rather than work witha group of discrete parts.PD-LD [email protected]
Temperature Controller
The LDT-5910C 32-W thermoelectric tempera-ture controller from ILX Lightwave Corp. incor-porates low-noise, bipolar current output with adigital proportional integral derivative controlloop for temperature control of laser diodes andoptoelectronic devices. For wavelength-sensitive
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applications, it provides long-term stability of±0.002 °C. It is compatible with thermistors, re-sistance temperature detectors, and LM335 andAD590 integrated circuit sensors. Linearizedthermistor sensor mode produces ±0.2 °C tem-perature accuracy from �30 to 85 °C with astandard 10-KO thermistor. Interlocks connectthe LDT-5910C to a laser diode driver and willdisable the laser output if the controller is dis-abled or is over the temperature limit. Analogvoltage input enables temperature sweeping ortuning without using a remote interface or frontpanel control. USB 2.0 and IEEE 488.1 general-purpose interface bus connections provide re-mote operation. LabView drivers for the LDT-5910C are available for download from thecompany’s website. ILX Lightwave [email protected]
Optical Oxygen and pH SensorsFor life sciences, pharmaceuticals, biotechnol-ogy, food and beverage processing, and moni-toring of fermentation processes, Ocean OpticsInc. has unveiled optical oxygen and pH sen-sors. Small and customizable, the fiber opticsensors perform in situ nonintrusive real-timemeasurements. Proprietary sensor coating ma-terials do not consume the sample and can beapplied to substrates such as probes, self-adhe-sive acrylic patches and microtiter wells. Oxygenpresence or pH can be visually determined bycolor change with a handheld LED, or a fluo-
rometer can be used to make exact measure-ments. An oxygen-sensitive fluorophore or pHindicator dye is trapped in a sol-gel host matrixthat can be applied to the tip of a fiber, an ad-hesive membrane such as a patch, or a flat sub-strate such as a cuvette. The indicator materialschange optical properties in response to specificanalytes in their environment, and electronicsmeasure the response. Ocean Optics [email protected]
LEDs
Avago Technologies’ ASMT-FJ70 and ASMT-FG70 series compact LEDs reduce space re-quirements for designing autofocus auxiliaryflash functionality into digital cameras. Suppliedin a thin, environmentally friendly surface-mount 3.6 � 3.2 � 3.4-mm package, they pro-duce the brightness needed for autofocus in
dark settings. They use a clear, nondiffused lensto produce high luminous intensity within a nar-row radiation pattern. The ASMT-FJ70 devicesare orange, and the ASMT-FG70 are green aux-iliary flash LEDs. ASMT-FJ70 uses AlInGaP ma-terial and features a 12° viewing angle, whileASMT-FG70 uses InGaN and provides a 14°viewing angle. Both produce high light outputover a range of drive currents. The narrowviewing angles deliver the long-distance illumi-nation and narrow beam pattern required forautofocus auxiliary flash. The LEDS are housedin a lead-free RoHS 6-compliant package andoperate from �40 to 85 °C. Avago [email protected]
Kinetic Microspectroscopy
Craic Technologies Inc. has added kinetic spec-troscopy capabilities to its 20/20 Perfect Vision
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UV-VIS-NIR microspectrophotometer. The system monitors the full-rangespectra of a microscopic sample area over time and plots the results.Analysis of samples can be done by absorbance, reflectance and opticalemission from the deep-UV to far into the near-infrared spectral regionsand over a range of time periods. Applications include biological time-re-solved analysis, measuring the degradation of LEDs over time, and mea-suring chemical reactions on metallic films. Time-resolved spectra of mi-croscopic sample areas can be analyzed with multiple spectroscopic tech-niques in the laboratory or manufacturing facility. The microspectropho-tometer delivers high spatial resolution and sensitivity. It integrates ahigh-speed spectrophotometer with a UV-VIS-NIR range microscope andeasy-to-use software. The instrument can create 3-D maps in which X andY are the spectrum and Z is the time domain.Craic Technologies [email protected]
MicroscopesOlympus Europa Holding GmbH’s CX22 series microscopes provide a large field ofview. Viewing height can be set easily to accommodate multiple users. Ergonomicallydesigned, they feature a lock in the upperstage to protect objectives and specimensfrom damage during focusing, and a wire-driven stage for smooth operation. The eye-pieces, objectives and condenser are se-cured to the microscope frame, preventingaccidental loss or damage. The power cordcan be wound around a hanger provided atthe rear of the system, facilitating transportand storage. The series also includes the CX22LED microscope, whichprovides long service life and offers low power consumption and naturalcolor tones. The CX22 uses a halogen lamp, which enables easy intensity
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adjustment and facilitates observation of imageswith faithful color reproduction. Objectives, eye-pieces and observation tubes are anti-fungus-treated for use in humid environments. Olympus Europa Holding [email protected]
Single-Mode Laser Diodes
Intense Inc. has released a 300-mW version of its Series 6030 and Series 6130 ultrahigh-power, high-brightness single-mode laserdiodes. Designed for defense, medical andprint/imaging applications such as spectros-copy and industrial coding, they are available in 980-, 830-, 808-, 785- and 780-nm wave-lengths. They are based on proprietary andpatented Quantum Well Intermixing technology,which increases brightness and reliability whileeliminating problems associated with cata-strophic optical mirror damage. The new wave-lengths and ultrahigh power are driving newuses in illumination, life sciences and atomicclock applications. The diodes offer high electri-cal conversion efficiency in a range of operatingtemperatures from 25 to 50 °C. They are avail-able in free-space packages including 9-mm, C-mount and 5.6-mm, with pulse durationmodulation optional, and are offered in a vari-ety of standard beam divergences to match specific application requirements. Intense [email protected]
Turret Upgrade Kit
Prior Scientific Inc. has unveiled the HF6NTKNikon turret upgrade kit for new or existingNikon Model Ti-FLC-E motorized six-positionturrets. It enables users to upgrade their Ti-FLC-E turret so the unit can be regulated by the PriorProScan III controller, making the system com-patible with most major imaging software pack-ages. The kit, combined with the ProScan IIIcontroller, regulates the Ti-FLC-E at speeds ofup to 300 ms between adjacent cubes. It also
enables motorization of the Nikon Ti withoutthe need for the HUB-B motorization hub. Thekit is compatible with Prior’s PS3J100 interactivecontrol center and can be retroverted easily tothe Nikon Ti six-position motorized turret’s orig-inal manufacturer’s specifications. Prior Scientific [email protected]
Metrology Software
IK5000 version 2.96 of PC-based Quadra-Cheksoftware from Heidenhain Corp. performs 2-and 3-D measurement. It introduces 3-D profil-ing capabilities that provide measurement andgraphic evaluation of 3-D contours using multi-sensor and tactile measuring machines. Thisnew option, used for profile measurements, imports a 3-D CAD file and compares it withthe actual measured part. Parts programmingimprovements support compensation for thethermal behavior of products that experienceshrinkage or growth during manufacture. Theradial and palletized methods of automaticparts programming routines help users whenthere are common features or parts that repeatangularly, around a datum or based upon apalletized grid layout. The palletized grid func-tionality allows the user to graphically selectwhich parts in the grid are required for mea-surement, and to run the program in those lo-cations only. The software is compatible with32-bit Windows 7, Windows XP and WindowsVista operating systems.Heidenhain [email protected]
Optical Engines
For applications requiring detection of light en-ergy at multiple wavelengths, Newport Corp.has released the OptoFlash miniature multi-channel spectrometer engines. The demultiplex-ing devices are configured with as many as 10wavelength channels, selected from 24 standardoptions ranging from 200 to 900 nm. Devel-oped for clinical chemical analyzers, they pro-
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vide high speed and high linearity with minimalstray light, as well as simultaneous opticaltransmission information for each wavelengthchannel, making them suitable for use in OEMapplications that require a small (51 � 16 � 25mm) and lightweight (30 g) single-package de-vice. They include silicon detectors, beam steer-ing optics and optical filters manufactured usingproprietary Stabilife optical coatings. The 40-pindual in-line package reduces instrument size,weight and complexity. The optical engines aresuitable for spectroscopy instruments designedfor immunodiagnostic testing, environmentalmonitoring and colorimetry. Newport [email protected]
Femtosecond Fiber LaserThe Femtolite HX-150 is the latest addition toImra America Inc.’s femtosecond fiber laser series. It emits at 1620 and 810 nm, with up to ≥200 mW at 1620 nm and up to ≥150 mWat 810 nm, or simultaneous emission at bothwavelengths. A slider bar enables continuousadjustment of the two signals’ average power.Applications include multiphoton fluorescencemicroscopy, second-harmonic imaging, tera-hertz wave generation and detection, laser lithography and ultrafast spectroscopy. With dimensions of 23 � 19.3 � 7.6 cm and a con-troller size of 30.7 � 20.7 � 13.5 cm, the laserintegrates into complex systems or OEM prod-ucts. Operation is done either directly from the
front panel controls or remotely via an RS-232interface. The fiber-based design ensures thatno adjustment, alignment or optical tweaking isrequired. Imra America [email protected]
Thermal Detector
The BeamTrack 3A-QUAD manufactured byOphir Photonics is a high-sensitivity thermal de-tector that combines power, energy and positionfunctions in a compact laser sensor. It measures
power from 100 µW to 3 W and energy from 20 µJ to 2 J, and tracks beam position down to0.1 mm. The beam position measurement func-tion allows tracking of beam wander as thebeam drifts from its initial position. The detectorhas a 9.5-mm aperture and measures from 190nm to 20 µm. BeamTrack sensors divide thesensor signal into quadrants, measuring andcomparing the output to determine the positionof the center of the beam. The sensor operateswith the company’s Nova II and Vega smart dis-plays and Juno PC interface. Each display fea-tures a “smart connector” interface that auto-matically configures and calibrates the displaywhen plugged into one of the company’s meas-urement heads.Ophir [email protected]
Digital Proximity SensorThe MAX44000 digital ambient-light and infra-red proximity sensor from Maxim IntegratedProducts Inc. detects light as a human eye does.The integrated circuit incorporates three opticalsensors, two analog-to-digital converters anddigital functionality into a 2 � 2 � 0.6-mmpackage. The sensor is suitable for touch-screenapplications, including smartphones, portabledevices, industrial sensors and presence detec-tion. Once a sensed signal is received, it is runthrough a DC ambient infrared rejection front-end circuit and sent to an analog-to-digital con-verter, allowing the sensor to operate in the
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presence of DC infrared radiation. By using asingle-pulse technique for pulsing the externalinfrared LED, it is immune to fixed-frequency ex-ternal infrared radiation. Proprietary BiCMOStechnology enables integration of the two photo-diodes and an optical filter to reject UV and IRlight. The sensor is offered in a lead-free, six-pin ultrathin dual flat no-lead package. Maxim Integrated Products [email protected]
Interference Filters
Photolithographic filters are used in applicationswith LSI and LCD steppers in which high-powermercury vapor lamps are employed for illumi-nation. The narrow bandpass filters produce analmost monochromatic radiation, allowing highresolution to be achieved in the target. LaserComponents GmbH’s partner Omega Opticalhas revised its i-line bandpass filters. The filterdesigns are now available based on dual mag-netron reactive sputtering coating, improvingboth the intensity of the i-line and its homo-
geneity in the photolithographic process. Onenew product from Omega is of interest for microelectromechanical systems production. MicroChem Corp., manufacturer of the SU-8photoresist, recommends that UV radiationbelow 350 nm be blocked to produce perpendi-cular structures. The PL-360-LP from the maskaligner series is suited to this application. All fil-ters are available from Laser Components.Laser Components [email protected]
Benchtop Raman Spectrometer
BaySpec Inc. has released the research-gradebenchtop RamSpec 1064-nm Raman spectrom-eter, which delivers high sensitivity and spectralresolution at wavelengths up to 1700 nm. Alighttight sampling chamber improves ease andaccuracy of sample measurements. Integrateddeep-cooled InGaAs array detectors and multi-ple volume phase gratings customized for each
wavelength provide maximized light throughput.Without any interferometric mechanical movingparts, it is designed for long-term stability, rug-gedness and automated push-button operation.With 1064-nm excitation, it is suitable for use incell biology, forensics, materials science andfood analysis. Features include a spectral rangefrom 150 to 3200 cm�1; spectral resolution of 4cm�1; automated wavelength calibration; com-pact size for portability; and customization withvarious fiber optic probes. BaySpec [email protected]
Thermal Imaging SoftwareFlir Advanced Thermal Solutions’ ResearchIRsoftware performs advanced thermal patternanalysis, viewing, recording and storage of im-ages at high speed, postprocessing of fast ther-mal events, and generation of time-temperatureplots from live images or recorded sequences. Itincludes a facility to set up start/stop recordingconditions, analyze data with an unlimited num-ber of functions, organize files, take a closelook at images with zoom and pan controls,and set up multiple user-configurable tabs forlive images, recorded images or plotting. Formore advanced thermal analysis, the company’sResearchIR Max has those features plus facilitiesfor pre- and posttriggering, tools for mathemat-ical processing and image filtering, radiometricdigital detail enhancement and support for par-allel recording using multiple cameras. Used
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with a Flir thermal imaging camera, ResearchIRsoftware allows researchers to make small tem-perature differences visible and to thoroughlyanalyze thermal processes in real time.Flir Advanced Thermal [email protected]
Wide-Emission IR LED
Opto Diode Corp. has announced the OD-850W infrared emitter. The GaAlAs LED fea-tures a wide emission angle, minimum opticaloutput of 30 mW, with 40 mW typical at 100mA, and a peak emission wavelength at 850nm. It is a replacement for the OD-880W IRLEDs, offering nearly double the output power,added stability and less degradation. The 850-nm wavelength is more closely matched to thepeak response of phototransistors and opto in-tegrated circuits, making them suitable for ap-plications such as photoelectric controls and op-tical encoders. Hermetically sealed, the TO-46package is designed with gold-plated surfacesand welded caps for durability. The IR LED of-fers continuous forward current at 100 mA and
peak forward current at 300 mA (absolute max-imum ratings at 25 °C). Storage and operatingtemperatures range from �40 to 100 °C, with a maximum junction temperature of 100 °C. Opto Diode [email protected]
Green Lasers for Surgery
Power Technology Inc. has launched a green-wavelength version of its PM series laser mod-ule. Designed for medical and surgical applica-tions, it performs better than red lasers ondark-colored or pigmented skin and on red tis-sue, and is easier to identify under the brightlights in the operating room. The PM visiblelaser diode is designed for use by OEM medicaland surgical manufacturers for integration intoexisting and prototype low-power lasers. It in-corporates a single-mode laser, single-elementglass collimating optics or line-generating op-tics, and the power supply into a single unit. Itmeasures 12.6 mm in diameter, is 50.93 mm
long and is available with input voltages rang-ing from 6 to 8 VDC. Optical output power andfine focus are adjustable, and optical outputpower digital control is available. The laser delivers output of 20 mW at 515 nm. Power Technology [email protected]
Scientific CMOS CameraAndor Technology plc has enhanced its Neo sci-entific CMOS (sCMOS) camera with faster sus-tained frame rates, better image quality, hard-ware pixel binning, flexible region of interestwith single-pixel granularity, accurate timestamp and improved global snapshot exposure.The 5.5-megapixel sCMOS sensor achieves 1 e� read noise at 30 fps, and the dual-ampli-fier architecture provides a dynamic range of30,000:1. The camera delivers deep-vacuumcooling down to �40 °C for low noise and mini-mal pixel blemish. It offers field-programmablegate array intelligence for stability and goodimage quality, coupled with 4-GB on-headimage memory that enables it to acquire ex-tended kinetic bursts at frame rates faster thanthe variable hard drive write speeds, eliminatingthe need for a PC. The laboratory camera issuitable for live-cell imaging. The sensor offersrolling and snapshot exposure modes, the latterenabling freeze-frame capture of fast-moving orfast-changing objects. Andor Technology [email protected]
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2-µm Fiber CouplersWith growing demand for products in the 2000-nm range, Phoenix Photonics Ltd. has extendedthe operational wavelength of its current selec-tion of all-fiber-based components with the in-troduction of 2-µm couplers. They are availablein 1 � 2, 2 � 2, tap and cascaded configura-tions. Proprietary technology facilitates theavailability of components built on single-modefiber specifically designed for optimized opera-tion in the 2000-nm-wavelength band. To opti-mize the performance of the fused couplers, thecompany has designed and built its own fusionrigs and developed the processing methods. Phoenix Photonics [email protected]
Optical Fiber StripperVytran LLC has unveiled the SAS-400 opticalfiber stripper, which uses hot sulfuric acid to re-move the protective coating from a fiber whilemaintaining the fiber’s intrinsic strength. Thecompany built it on the concept of its predeces-sor, the SAS-200, but with an increased empha-sis on use in manufacturing. Improvements include greater ease of use and enhanced ro-bustness. The new model features an intuitivegraphical user interface and improved operatorprotection. The automated system is intendedfor use in sensing, medical, telecommunica-tions, aerospace and research applications. Itcan remove a variety of coating types, includingacrylate and polyimide, and can strip a fiber
section up to 40 mm long. It can be used tocenter strip a fiber for fiber Bragg grating man-ufacture and for metallizing fiber sections.Vytran [email protected]
640 � 512 InGaAs Camera
Princeton Instruments’ PIoNIR:640 scientific-grade camera uses a deep-cooled InGaAs focalplane array and is designed for low-light near-infrared and short-wavelength infrared imagingand spectroscopy applications that require sen-sitivity from 0.9 to 1.7 µm. Applications includenanotube fluorescence imaging, photovoltaic(PV) inspection, semiconductor failure inspec-tion, singlet oxygen imaging, photolumines-cence imaging of PV materials, near-infraredfluorescence and absorbance, and deep-tissue
imaging. Thermoelectric cooling to �90 °C min-imizes thermal noise to achieve a good signal-to-noise ratio. The camera offers air or liquidcooling, or a combination of the two, for use inthermal- and vibration-sensitive environments.The Gigabit Ethernet interface enables remoteoperation and delivers a maximum rate of 110fps at full resolution. Proprietary LightField dataacquisition software controls all hardware fea-tures via an intuitive user interface and providesautomatic defect correction, exposure control upto minutes, and functions for capture and exportof imaging and spectral data. Princeton [email protected]
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b BRIGHT IDEAS
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b ANOTHER BRIGHT IDEA
Advertise your new product in Photonics Showcase or in the Spotlight section of Photonics Spectra.
Reach all of our readers in these low-cost, lead-generating features.
Call Kristina Laurin at (413) 499-0514, or e-mail [email protected].
312_Bright Ideas_Layout 1 2/22/12 4:08 PM Page 86
APRILFocus on Microscopy 2012 (April 1-4)Singapore. Contact Fred Brakenhoff, Universityof Amsterdam, +31 20 5255 189; [email protected]; www.focusonmicroscopy.org.
Photonix 2012 Expo & Conference (April11-13) Tokyo. Contact Mitsuru Takazawa, Reed Exhibitions Japan Ltd., +81 3 3349 8549;[email protected]; www.photonix-expo.jp/en.
Photovoltaics Summit 2012 (April 16-18)San Diego. Contact IntertechPira, a division of Pira International, +1 (202) 309-7296;[email protected]; www.photovoltaicsummit.com.
SPIE Photonics Europe (April 16-20)Brussels. Contact SPIE, +1 (360) 676-3290;[email protected]; spie.org.
Photomask Japan 2012 (April 17-19)Yokohama, Japan. Contact Photomask JapanSecretariat, +81 3 3219 3541; [email protected]; www.photomask-japan.org.
Photonics. World of Lasers and Optics 2012 (April 17-20) Moscow. Contact Liudmila V. Bedniakova, Laser Association (LAS), +7 (495) 333-0022;[email protected]; www.photonics-expo.ru/en.
META 2012, Third International Conference on Metamaterials, Photonic Crystals and Plasmonics (April 19-22) Paris. Contact Secretariat, +33 1 69 85 16 60; [email protected]; metaconferences.org.
Experimental Biology 2012 (April 21-25) San Diego. Contact Yvette Clark, Federation of AmericanSocieties for Experimental Biology, +1 (301) 634-7016; [email protected]; experimentalbiology.org.
SPIE Defense, Security + Sensing (April 23-27) Baltimore. Contact SPIE, +1(360) 676-3290; [email protected];spie.org.
Optics and Photonics International 2012 Congress & Exhibition (April 25-27) Yokohama, Japan. Includes Laser Expo 2012. Contact The Optronics Co. Ltd., +81 3 3269 3550; www.optronicsjp.com.
Advanced Optical Manufacturing and Testing Technologies 2012 (April 26-29) Xiamen, China. Contact Yang Li, [email protected]; Fax: +86 28 8510 0583; www.aomatt.org.
Biomedical Optics and 3-D Imaging: OSA Optics and Photonics Congress (April 29-May 2) Miami. Contact Optical Society of America, +1 (202) 223-8130;[email protected]; www.osa.org.
MAYCLEO: 2012 – Laser Science to Photonic Applications (May 6-11) San Jose, Calif. Conference on Lasers and Electro-optics. Contact Optical Society of America CustomerService – CLEO Management, +1 (202) 416-1907; [email protected]; www.cleoconference.org.
The Vision Show (May 8-10) Boston. Contact Automated Imaging Association, +1 (734) 994-6088; www.machinevisiononline.org.
Mfg4 (Manufacturing 4 the Future) Conference & Exposition (May 8-10)Hartford, Conn. Contact Society of Manufacturing Engineers, +1 (800) 733-4763;[email protected]; www.mfg4event.com.
AKL – International Laser Technology Congress (May 9-11) Aachen, Germany. Contact Silke Boehr, Fraunhofer Institute forLaser Technology ILT, +49 241 8906 288;[email protected]; www.lasercongress.org.
Quantum Interfaces: Integrating Light, Atoms and Solid-State Devices (May 14-15) Milton Keynes, UK. Con-tact Jon Mackew, Institute of Physics, +44 20 7470 4800; [email protected];www.iop.org.
Third International Topical Meeting on Optical Sensing and Artificial Vision(OSAV 2012) (May 14-17) St. Petersburg, Russia. Contact Igor Gurov, conference chairman, +7 812 571 6532; [email protected]; osav.spb.ru.
Sensor + Test 2012 (May 22-24)Nuremberg, Germany. Contact AMA Service GmbH, +49 50 33 96 39 0; [email protected]; www.sensor-test.com.
ANGEL 2012 – Second Conference on Laser Ablation and Nanoparticle Generation in Liquids (May 22-24)Taormina, Italy. Contact Silke Kramprich, EOS-Events & Services GmbH, +49 511 2788117; [email protected]; www.myeos.org/events/angel2012.
OPTATEC 2012 (May 22-25) Frankfurt, Germany. Contact P.E. Schall GmbH & Co. KG,+49 7025 9206 0; [email protected];www.optatec-messe.com.
XXII International Scientific and Engineering Conference on Photoelectronics and Night Vision Devices (May 22-25) Moscow. ContactAlexander I. Dirochka, State Scientific Center of Russian Federation, +7 499 374 81 20;[email protected]; www.orion-ir.ru.
BioMedOptTex Symposium (May 23-25) College Station, Texas. Contact Kristen Maitland, [email protected];biomed.tamu.edu.
Sixth International Conference onNanophotonics (ICNP) (May 27-30)Beijing. Contact Optical Society of America, +1 (202) 223-8130; [email protected]; icnp2012.pku.edu.cn.
JUNEDisplay Week 2012 (June 4-8) Boston. Contact Society for Information Display,
HAPPENINGSPAPERS
MIOMD-XI (September 4-8) Evanston, IllinoisDeadline: abstracts, April 4Papers are encouraged for MIOMD-XI, the 11th International Conference on Infrared Optoelectronics:Materials and Devices. Among topics to be considered are infrared emission in the areas of LEDs, and Fabry-Perot, external cavity and high-power distributed feedback lasers; infrared detection, including single-element and single-photon detectors, and multicolor detection and imaging; andmonolithic and heterogeneous integration of lasers, detectors and passive components. Contact Manijeh Razeghi, Northwestern University, +1 (847) 491-7251; [email protected];miomd-11.northwestern.edu.
SPIE Laser Damage (September 23-26) Boulder, ColoradoDeadline: abstracts, April 16SPIE is accepting papers for its Laser Damage conference, which addresses materials for high-powerand high-energy lasers. Topics to be discussed include photonics bandgap materials, multilayer thinfilms, nonlinear optical and laser host materials, fibers for high-power laser applications, measure-ment protocols, materials characterization, contamination of optical components, metamaterials and thermal management of high-power lasers. Contact SPIE, +1 (360) 676-3290; [email protected]; spie.org.
EOS Annual Meeting 2012 (September 25-28) Aberdeen, UKDeadline: abstracts, May 7The European Optical Society invites papers for EOSAM 2012. Contributions will be accepted for oral and poster presentations. The event will encompass topical meetings on biophotonics, siliconphotonics, nanophotonics and metamaterials, micro-optics, organic photonics and electronics, nonlinear photonics, and optical systems for the energy and production industries. Contact EOS –Events & Services GmbH, +49 511 2788 115; [email protected]; www.myeos.org.
87Photonics Spectra March 2012
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+1 (408) 879-3901; [email protected];www.sid.org.
3D Microscopy of Living Cells Course (June 9-21) and 3D Image Processing Postcourse Workshop (June 23-25) Vancouver,British Columbia, Canada. Contact James Pawley, University of Wisconsin-Madison, +1 (608) 238-3953; [email protected];www.3dcourse.ubc.ca/2012.
QIRT 2012: 11th Quantitative InfraredThermography Conference (June 11-14)Naples, Italy. Contact Secretariat, +39 0817685 184; [email protected]; www.qirt2012.unina.it.
Lasys 2012: International Trade Fair for System Solutions in Laser Material Processing (June 12-14) Stuttgart, Germany.Contact Meike Mayer, +49 711 18560, Ext. 2374; [email protected];www.messe-stuttgart.de.
euroLED 2012 (June 13-14) Birmingham, UK.Contact Michelle Cleaver, +44 121 250 3515;[email protected]; www.euroled.org.uk.
Third EOS Topical Meeting on TerahertzScience & Technology (TST 2012) (June 17-20) Prague, Czech Republic. A European Optical Society Event. Contact SilkeKramprich, EOS – Events & Services GmbH,
+49 511 277 2674; [email protected];www.myeos.org/events/tst2012.
Advanced Photonics Congress (June 17-21)Colorado Springs, Colo. Includes Access Networks and In-house Communications; Bragg Gratings, Photosensitivity and Poling in Glass Waveguides; Integrated Photonics Research, Silicon and Nano-Photonics; Photonic Metamaterials and Plasmonics; Nonlinear Photonics; Specialty Optical Fibers & Applications; and Signal Processing in Photonic Communications. Contact Optical Society of America, +1 (202) 223-8130;[email protected]; www.osa.org.
TechConnect World 2012 (June 18-21)Santa Clara, Calif. Contact Sarah Wenning, +1 (925) 353-5004; [email protected]; www.techconnectworld.com.
BIO International Convention (June 18-21)Boston. Contact Biotechnology Industry Organization, +1 (202) 962-9200; [email protected]; www.convention.bio.org.
Imaging and Applied Optics: OSA Optics & Photonics Congress (June 24-28)Monterey, Calif. Includes Applied Industrial Optics: Spectroscopy, Imaging, and Metrology;Computational Optical Imaging and Sensing;Imaging Systems Applications; Optical Fabrica-tion and Testing; Optical Remote Sensing of
the Environment; and Optical Sensors. Contact Optical Society of America, +1 (202)223-8130; [email protected]; www.osa.org.
JULY2012 Astronomical Telescopes + Instrumentation (July 1-6) Amsterdam. Contact SPIE, +1 (360) 676-3290; [email protected]; www.spie.org.
39th COSPAR Scientific Assembly (July 14-22) Mysore, India. Contact COSPAR(Committee on Space Research) Secretariat,+33 1 44 76 75 10; [email protected];www.cospar-assembly.org.
Lasers in Medicine & Biology Conference(July 22-27) Holderness, N.H. Contact HollyTobin, Gordon Research Conferences, Fax: +1(401) 783-7644; [email protected]; www.grc.org.
M&M 2012: Microscopy & Microanalysis(July 29-Aug. 2) Phoenix. Contact MicroscopySociety of America, +1 (703) 234-4115; [email protected]; www.microscopy.org.
88
h HAPPENINGS
Photonics Spectra March 2012
For complete listings, visitwww.photonics.com/calendar
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June Content Focus: Food & DrinkSpotlight: Imaging Components & SystemsAd close: April 25, 2012
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aADVERTISER INDEX aADVERTISER INDEX
89Photonics Spectra March 2012
Photonics Media Advertising Contacts
Please visit our websitePhotonics.com for all your marketing needs.
Ken TyburskiDirector of SalesVoice: +1 (413) 499-0514, Ext. 101Fax: +1 (413) [email protected]
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Northern CA, AK, NV, Pacific Northwest,Yukon & British Columbia Joanne C. GagnonRegional ManagerVoice: +1 (413) 499-0514, Ext. 226Fax: +1 (413) [email protected]
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Eastern CanadaMaureen Riley MoriartyRegional ManagerVoice: +1 (413) 499-0514, Ext. 229Fax: +1 (413) [email protected]
Europe, Israel & South Central USOwen BrochRegional ManagerVoice: +1 (413) 499-0514, Ext. 108Fax: +1 (413) [email protected]
Austria, Germany & LiechtensteinOlaf KortenhoffVoice: +49 2241 1684777Fax: +49 2241 [email protected]
Asia (except Japan)Hans ZhongVoice: +86 755 2872 6973Fax: +86 755 8474 [email protected]
JapanScott ShibasakiVoice: +81 3 5225 6614Fax: +81 3 5229 [email protected]
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Mailing addresses:Send all contracts, insertion orders and advertising copy to:Laurin PublishingPO Box 4949Pittsfield, MA 01202-4949
Street address:Laurin PublishingBerkshire Common, 2 South St.Pittsfield, MA 01201Voice: +1 (413) 499-0514Fax: +1 (413) [email protected]
Aero Research Associates Inc. ................... 28www.aerorese.com
Andor Technology .................74www.andor.com
Applied Scientific Instrumentation ....................34www.asiimaging.com
Argyle International ...............26www.argyleoptics.com
Automated Imaging Association .........................43www.visiononline.org
B&W Tek ................................7www.bwtek.com
Bayspec Inc. ..........................79www.bayspec.com
Bristol Instruments Inc. ............49www.bristol-inst.com
Castech Inc. ...........................66www.castech.com
China Daheng Group Inc. ..........................82www.cdhcorp.com
Coherent Inc. .....................9, 33www.coherent.com
Cooke Corporation Ltd. ..........19www.cookecorp.com
CVI Melles Griot ....................32www.cvimellesgriot.com
Directed Energy Inc. ...............56www.ixyscolorado.com
DRS Technologies Inc. ............15www.drs.com
Edmund Optics .................20-21www.edmundoptics.com
EMD Millipore Corporation ........................39www.emdchemicals.com
Energetiq Technology Inc. .......12www.energetiq.com
Esco Products Inc. ..................18www.escoproducts.com
Forth Dimension Displays Ltd. .......................75www.forthdd.com
Horiba Scientific ....................24www.picocomponents.com
ILX Lightwave Corp. ...............35www.ilxlightwave.com
Iridian Spectral Technologies .......................74www.iridian.ca
Julabo USA Inc. .....................75www.julabo.com
Laser Institute of America .........................80www.icaleo.org
Lee Laser Inc. .........................44www.leelaser.com
Lightmachinery Inc. ..........26, 30www.lightmachinery.com
Lightworks Optics Inc. ..........................31www.lwoptics.com
Luminit LLC ............................75www.luminitco.com
Master Bond Inc. ...................30www.masterbond.com
Mightex Systems ....................34www.mightexsystems.com
New Focus, A Newport Corporation Brand ..............................CV4www.newport.com
Newport Corp. ..........29, 77, 81www.newport.com
nm Laser Products Inc. ............88www.nmlaser.com
Nova Sensors, a Teledyne Majority Owned Company ................41www.novasensors.com
Novotech Inc. ........................62www.novotech.net
Nufern ................................CV2www.nufern.com
Ocean Optics ........................27www.oceanoptics.com
OPCO Laboratory Inc. ...........23www.opcolab.com
Photonics Media .......46, 57, 74,81, 85, 88
www.photonics.comPhotonis USA Inc. ..................60
www.photonis.comPI
(Physik Instrumente) L.P. .......37www.pi.ws
Pico Electronics Inc. ................14www.picoelectronics.com
Power Technology Inc. ...........11www.powertechnology.com
Prior Scientific Inc. .................86www.prior.com
Research Electro-Optics .....................25www.reoinc.com
Ross Optical Industries ...........40www.rossoptical.com
Scanlab AG ............................8www.scanlab.de
Schott North America Inc. Lighting and Imaging Division ............................CV3www.us.schott.com/lightingimaging
Siskiyou Corporation ..............22www.siskiyou.com
Society of Electrical & Electronic Engineers in Israel ..............................83www.seeei.org.il/english/html
Society of Manufacturing Engineers ...........................84www.mfg4event.com
Spectra-Physics, A Newport Corporation Brand ...................................6www.newport.com
SPIE International Society for Optical Engineering .......53www.spie.org/aboutdss
Stanford Research Systems Inc. ..........................3www.thinksrs.com
StellarNet Inc. ........................42www.stellarnet-inc.com
Tohkai Sangyo Co. Ltd. ..................86www.peak.co.jp
Toptica Photonics Inc. ......................75www.toptica.com
Vat Inc. .................................74www.vatvalve.com
Vivid Engineering ...................74www.vividengineering.com
Xenics NV .............................75www.xenics.com
Zygo Corp. ...........................13www.zygo.com
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p PEREGRINATIONS
Out of the blue, into the office
Working outdoors in the sunshinewith blue skies and fluffy whiteclouds overhead – it sounds a
little like heaven, doesn’t it? Except whenrain falls, snow blows or wind gusts, ofcourse. Skylights can provide much thesame effect – for the top floor of a build-ing – on a sunny day.
But a new “virtual sky” ceiling lightingsetup gives office workers the feeling ofbeing outside, even on the first floor andeven when the weather outside is frightful.The idea is to boost productivity and well-being.
The setup, developed by Fraunhofer Institute for Industrial Engineering IAO in Stuttgart in collaboration with LEiDsGmbH & Co. KG of Backnang, both inGermany, simulates sunlight along withpassing clouds. To do this, the researchersstudied the natural light spectrum and thespeed at which it changes as breezes playwith clouds.
The celestial ceiling consists of 50 �50-cm tiles, with each one comprising aboard with 288 LEDs, said Matthias Bues,head of the Visual Technologies Compe-tence Team at Fraunhofer IAO. A matte-white diffuser film beneath the LEDs produces the effect of uniform lightingthroughout the room. Red, blue-green andwhite LEDs enable the full light spectrumto shine forth.
The LEDs enable simulation of the dy-namic changes in natural lighting withoutmaking the artificiality obvious to thenaked eye, Bues said.
In a pilot study, the virtual sky was wellreceived. For four days, 10 participantsworked under a 30 � 60-cm lighting sur-face. The lighting was motionless on thefirst day, fluctuated moderately on the sec-ond day and changed rapidly on the third.A total of 80 percent of the volunteerschose the fast, dynamic lighting optionwhen given their choice of illuminationfor the fourth day.
The prototype “sky” contains 34,560LEDs spanning an area of 34 sq m. Theceiling can light up with an intensity ofmore than 3000 lux, but 500 to 1000 luxcreates a comfortable level of illumina-tion, the researchers say.
There has been some interest in the lu-minous ceiling for conference rooms.Bringing the outdoors in currently has ahigh price tag – about $1300 per squaremeter – but the cost could come down ifdemand and production increase.
90 Photonics Spectra March 2012
Caren B. [email protected]
Top image: Light from an artificial sky, such as thatproduced by these ceiling panels, could promote increased productivity in office settings. Bottomimage: A behind-the-scenes view of the LED panelsbeneath a diffuser screen, which helps to create uniform lighting for a skylike office ceiling.
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