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1
Optical Noise-Free
Microphone (ONFM)
Prof. Mordechai Segev, TechnionProf. Israel Cohen, Technion
.
Eng. Zvika KatzDr. Rami Aharoni
Ofer Pillar
. 2
Overview Optical microphone that filters out background noise
Small standoff implementation: mobile communication
headsets professional applications
Large standoff implementation: directional hearing aids non-contact medical monitoring
. 3
ONFM TechnologyA high-sensitivity, optical sensor for acoustic vibrations in the body, with background isolation
Blue-tooth head-sets, and cellular phones
As well as high performance audio headsets
Thus far focused on small standoff applications in the mobile communication markets:
. 4
Value PropositionConsumer:Speaking over mobile/ VoIP w/o background interference, and w/o disclosing location:Be heard clearly in a noisy environment
(outdoor, in a car, on the shop floor)Conference calls that do not require mutingWorking from home with children playing in
backgroundSafe usage of a street café as an officeImproved voice recognition functions
. 5
Professional:User can speak in a noisy environment without interference [“No boom Headset”]:Broadcasters on streets or in noisy sport eventsHeavy equipment operatorsCall service centersAviationFactory floorHomeland securityMilitary
Value Proposition
. 6
ONFM Concept
. 7
ONFM – Performance The optical sensor provides high background
suppression (potentially >70dB, demonstrated
>50dB) Achieves high sensitivity (<<1nm); detects
voice at different locations on head Complement high-frequency components by
eitherSpectral augmentation – synthesizing hi-freq
components from pre-recorded sound librarySignal fusion with standard microphone
. 8
Blue-tooth Headset
Eliminates monotonous, intermittent and abrupt noise
Voice “Beep” H. Clap
Standard Set
ONFM
2/4/08 . 9
ONFM – Prelim DemoHand-clapping:
fused sensor algo. essentially removes noise.
Further development to enhance performance and evaluate spectral augmentation
Input
Output
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Accomplishments
Small standoff ONFM concept demonstrated
Demo of high-fidelity, high-suppression of intermittent widebandnoise
Construction of small devicesDemo loose physical contactPotentially compact, low cost, low power
. 11
Patents
Three patent applicationsBasic concept – favorable PCT search
report, national phaseLow-cost, small standoff device [IL, PCT]High performance large standoff device [IL,
PCT]
Additional patents in preparationLarge standoff, speckle corrected device
. 12
Potential Markets
High end Mobile phones Headsets: mobile (or land line)
phones (Bluetooth), VoIP, Gaming Professional microphones: News
Reporters, Sport commentary Professional noise canceling
headsets, Call centers, aviation, factory floor
Video Conferencing
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Other Potential Markets– large standoff
Directional hearing aids (allows hearing-aid users to discriminate between the voice of the person speaking to them and background conversations in a crowd)
Distant mics for Security camera’s
22/3/08 . 14
Summary
Revolutionary opto-acoustic technology Huge market potentialDemonstrated feasibility of conceptTechnology suitable for mobile headsets
and additional products for directional hearing aids and security applications
Complex Nonlinear Opto-Fluidity
To be Submitted to Nature
Carmel Rotschild, and M. Segev Physics Department, Technion-Israel Institute of Technology, Haifa 32000, Israel
D. N. ChristodoulidesCollege of Optics & Photonics-CREOL, University of Central Florida
MicroCHIPS: micro-reservoirs which can be loaded with medication,implanted in the patient's body and administering the medication in a timed manner
Light
microchip, which can continuouslymonitor sugar level of diabetes patients
Current opto-fluid technology
D. Psaltis, S. R. Quake & C.Yang, NATURE, 442, 27 2006
Opto-fluidity state of the art
Physical mechanism
Light
High indexHighly transparent
Nano-Particles
Low index Highly transparent
Liquid
Induced polarizability
Gradient force
Drag transfer momentum from particles to fluid
Distribute particles
Distribute n
Optical force bend light
Gradient Force
b
p
n
n
n
nm
1
2
oEp
2
12
221
3
m
mna
is the polarizabilityIF
4
ccerAtrE tj .2
1,
We have found a way to induce :strong force, and low mobility of particles,resulting High momentum transfer to liquid
Motivation: Use light to control mechanical properties of fluids
How? transfer momentum from light to fluid
Absorption : Limits light propagation + thermal effect
Physical processes Electromagnetic gradient force
INF 4
Force per volume
N: particles density
Force per particle
IF 4
Overview: Opto-HydrostaticsLight
Particles
Induced polarizability
Gradient forceDistribute n
Optical force bend light
Four-wave mixing in artificial Kerr MediaP.W. Smith, A.Ashkin, and W.J. Tomlinson, Opt. Lett. , 6, 284 (1981)
Self focusing in artificial Kerr media A.Ashkin, J.M. Dziedzic, and P.W. Smith, Opt. Lett. , 7, 276 (1982)
Physical mechanism
Light
High indexHighly transparent
Nano-Particles
Low index Highly transparent
Liquid
Induced polarizability
Gradient force
Drag transfer momentum from particles to fluid
Distribute particles
Distribute n
Optical force bend light
We have found a way to induce :
strong optical force, and large drag of
particles,
resulting efficient momentum transfer to
liquid
Quantum dots with ligands = “nano – medusa” structure
High index contrastSmall core: Low scatteringLong ligands: Low mobility (high drag)
Advantages:
Transfer angular momentum from the light to the liquid and back
Archimedes Pump: pulling liquid by light
Pipette diameter:0.7 mm
Archimedes Pump: Lifting liquid by light
Intensity structuredesign for lifting
Optically induced surface tension Low power Low powerHigh power High power
angle
contact
gravityg
density
tension
surface
heighth
grh
:
:
:
:
:
cos
Light / surface interaction
Suggesting chaos:Spectrum expands in time
m fromThresholddistance
Future plans
•Methodological experiments on-Optically induced surface tension (Hydrostatic)-Optically induced n (Hydrostatics)-Material optimization
•Theoretical model•Optically induced self assembly •Optical control over local chemical reactions•Turbulence / Laminar transient coupled•Optically induced transparency
to nonlinear optics
A Functionalized CdSe Quantum Dot - Carbon Nanotube Heterostructure
Stanislaus S. Wong
Optically induced catalysis
Optical setup Spatial intensitydistribution Self-assembly
2D
3D
Optically controlled self-assembly
Optically induced transparency
33.1,56.1,50
105.3,532.0 4
bp nnnma
fm
33.1,1,50
10,532.0 3
bp nnnma
fmPolystyrene nano-suspensions Air bubbles nano-suspensions
m
Pro
pag
atio
n d
ista
nce
in m
m
losses =20%
High power
m
losses=13%
Pro
pag
atio
n d
ista
nce
in m
m
Low power
m
Pro
pag
atio
n d
ista
nce
in m
m
losses =20%
High power
m
losses=97%
Pro
pag
atio
n d
ista
nce
in m
m
Low power
R. El-Ganainy, C. Rotschild, M. Segev, and D. N. Christodoulides, Optics Express, 15, 10207(2007)
; Ibid, Opt. Lett., 32, 3185 (2007).
ConclusionsFirst observation of symbiotic nonlinear dynamics
of fluids and light acting together: complex nonlinear Opto-fluidity.
Challenges:•Theoretical model•Sub-wavelength features•Optically induced self assembly •Optical control over local chemical reactions•Turbulence / Laminar transient coupled
to nonlinear optics
Thank you