Multiplexed Sensor Array Patents (Class 356/478)
  • Patent number: 8797541
    Abstract: A method, apparatus and optical network for obtaining a signal from a sensor in a fiber optic cable at a downhole location is disclosed. A reference signal is propagated through the fiber optic cable. A beam of light is received from the fiber optic cable, wherein the beam of light includes the propagated reference signal and the signal from the sensor generated from an interaction of the sensor and the reference signal. The propagated reference signal is obtained from the received beam of light. The signal from the sensors is obtained by sampling the received beam of light using the obtained propagated reference signal.
    Type: Grant
    Filed: July 11, 2011
    Date of Patent: August 5, 2014
    Assignee: Baker Hughes Incorporated
    Inventors: Roger Glen Duncan, Brooks A. Childers
  • Publication number: 20140139843
    Abstract: An apparatus for detecting a deflection of a beam, the apparatus comprising a beam having a first side and a second side; and a grating structure positioned adjacent the second side of the beam, the grating structure including an interrogating grating coupler configured to direct light towards the beam; wherein the beam and the interrogating grating coupler form a resonant cavity, and light input to the resonant cavity is modulated according to the deflection of the beam.
    Type: Application
    Filed: December 30, 2013
    Publication date: May 22, 2014
    Applicant: University of Western Australia
    Inventors: John Marcel Dell, Mariusz Martyniuk, Adrian John Keating, Gino Michael Putrino, Lorenzo Faraone, Dilusha Silva
  • Patent number: 8670124
    Abstract: An apparatus, method and computer program wherein the apparatus includes at least one interferometer where the at least one interferometer is configured to cause interference of an electromagnetic input signal; wherein the at least one interferometer is configured to receive at least one sensor input signal from at least one sensor such that the sensor input signal controls the interference of the electromagnetic input signal by the at least one interferometer; wherein the at least one interferometer is configured to provide a plurality of outputs where each of the plurality of outputs is provided by the at least one interferometer responding to the at least one sensor input signal with a different sensitivity; and at least one detector configured to detect the plurality of outputs of the at least one interferometer and provide a digital output signal indicative of the at least one sensor input signal.
    Type: Grant
    Filed: January 31, 2012
    Date of Patent: March 11, 2014
    Assignee: Nokia Corporation
    Inventors: Antti Niskanen, Hongwei Li
  • Patent number: 8638444
    Abstract: A method, system and apparatus for obtaining a parameter of interest relating to a wellbore is disclosed. A fiber optic cable having a plurality of sensors is disposed in the wellbore, wherein the plurality of sensors have reflectivity values configured to provide improved signal-to-noise ratio compared to signal-to-noise ratio of a plurality of sensors having substantially same reflectivity values. Light is propagated into the fiber optic cable from a light source and signals are received at a detector from the plurality of sensors in response to interaction of the propagated light with the plurality of sensors. A processor may be used to obtain the parameter of interest from the received signals. The fiber optic cable may be coupled to a member in the wellbore, wherein the parameter of interest is related to the member.
    Type: Grant
    Filed: January 11, 2011
    Date of Patent: January 28, 2014
    Assignee: Baker Hughes Incorporated
    Inventors: Roger Glen Duncan, Brooks A. Childers, Daniel S. Homa
  • Patent number: 8597578
    Abstract: The present invention is directed to an assembly for use in detecting an analyte in a sample based on thin-film spectral interference. The assembly comprises a waveguide, a monolithic substrate optically coupled to the waveguide, and a thin-film layer directly bonded to the sensing side of the monolithic substrate. The refractive index of the monolithic substrate is higher than the refractive index of the transparent material of the thin-film layer. A spectral interference between the light reflected into the waveguide from a first reflecting surface and a second reflecting surface varies as analyte molecules in a sample bind to the analyte binding molecules coated on the thin-film layer.
    Type: Grant
    Filed: August 19, 2011
    Date of Patent: December 3, 2013
    Assignee: Access Medical Systems, Ltd.
    Inventors: Hong Tan, Yushan Tan, Erhua Cao, Min Xia, Robert F. Zuk
  • Patent number: 8508747
    Abstract: Systems and methods for providing trigger signals in an optical interrogator, wherein multiple triggers are generated within each period of a varying reference signal, and wherein the triggers are evenly spaced according to the wavenumber of the reference signal. In one embodiment, an optical frequency domain reflectometry system provides a laser beam to a reference interferometer to produce a reference signal. This signal is passed through a 4×4 optical coupler which splits the signal into a first signal and a second signal that is 90 degrees out of phase with the first signal. These signals are converted to electrical signals, and a trigger unit generates triggers at points at which the two electrical signals have zero-crossings, and at which the magnitudes of the signals are equal. The resulting triggers remain evenly spaced within the period of the reference signals, even when the period is changed.
    Type: Grant
    Filed: February 17, 2010
    Date of Patent: August 13, 2013
    Assignee: Baker Hughes Incorporated
    Inventors: Brooks A. Childers, Roger G. Duncan
  • Publication number: 20130194580
    Abstract: A multiple optical channel autocorrelator based on an optical fiber circulator includes a broad-band light source, at least an optical-fiber sensor array, an adjustable multiple light beams generator, at least an optical fiber circulator and at least a photoelectric detector. The optical-fiber sensor array is composed of the sensing fibers connected end to end. The online mirrors are formed by the connecting end faces of the adjacent fibers. The adjustable multiple light beams generator includes a fixed arm and an adjustable arm. The optical path difference between the fixed arm and the adjustable arm is adjustable in order to match the optical path of each sensor in the sensor array. The optical fiber circulator couples the signals generated by the multiple light beams generator to the sensor array, and couples the signals returned by the sensor array to the photoelectric detector. The photoelectric detector is connected to the optical fiber circulator.
    Type: Application
    Filed: October 8, 2010
    Publication date: August 1, 2013
    Applicant: Harbin Engineering University
    Inventors: Libo Yuan, Jun Yang, Ai Zhou
  • Publication number: 20130070254
    Abstract: An interferometer is provided that includes a first path and a second path. The first path is configured to propagate an electro-magnetic signal at a first wavelength. The second path is configured to convert a portion of the electro-magnetic signal from the first wavelength to a second wavelength for processing and is configured to convert the portion of the electro-magnetic signal from the second wavelength back to the first wavelength for interference with the electro-magnetic signal of the first path. The first wavelength may be an optical wavelength or any other suitable wavelength of the electro-magnetic spectrum. The second wavelength, which is different than the first wavelength, also may be any suitable wavelength of the electro-magnetic spectrum.
    Type: Application
    Filed: September 16, 2011
    Publication date: March 21, 2013
    Inventor: Peter Winzer
  • Patent number: 8379217
    Abstract: An optical sensor interrogation system comprises: a multi-frequency optical source configured to generate an optical interrogation signal, at least one optical sensor configured to filter light at a wavelength corresponding to a value of a sensed parameter and generate an optical sensor data signal, a photodetector configured to detect a reference signal and the optical sensor data signal and generate an electrical difference frequency signal corresponding to a wavelength difference between the reference signal and the optical sensor data signal, and an electrical frequency measurement module configured to measure the electrical difference frequency.
    Type: Grant
    Filed: March 23, 2006
    Date of Patent: February 19, 2013
    Assignee: General Electric Company
    Inventors: Glen Peter Koste, Richard Louis Frey, Joseph Alfred Iannotti
  • Patent number: 8332016
    Abstract: The present invention improves projection displays of volume data. Using the Minimum Intensity Projection (MinIP), fluid filled regions or other regions of hyporeflective tissue are displayed. By limiting the projection to partial volumes within the volume, differences in the scattering intensity within specific regions are isolated. In this way, hyperreflectivity of weakly scattering tissue can be assessed.
    Type: Grant
    Filed: August 4, 2009
    Date of Patent: December 11, 2012
    Assignee: Carl Zeiss Meditec, Inc.
    Inventor: Paul F. Stetson
  • Publication number: 20120301072
    Abstract: An optical fibre sensor assembly comprises a source of a plurality of different frequency substantially monochromatic signals (1, 2, 3, 4); a modulator connected to the output of the source to produce a train of output pulses of the monochromatic signals; a plurality of sensor sub-assemblies connected to the output of the modulator, each sub-assembly comprising an optical drop multiplexer (ODM) (13), a sensor array (14) comprising a plurality of sensor elements and an optical add multiplexer (OAM) (15); a wavelength demultiplexer (WDM), having an input coupled to the sub-assemblies output; a plurality of detectors, each detector having an input connected to receive a respective output of the WDM and providing at an output thereof a signal corresponding to a respective frequency of the modulated monochromatic signals; and an interrogation system, having a plurality of inputs connected such that each input receives the output signal from a respective detector.
    Type: Application
    Filed: July 26, 2012
    Publication date: November 29, 2012
    Applicant: QinetiQ Limited
    Inventor: Geoffrey A. Cranch
  • Publication number: 20120281234
    Abstract: In an embodiment, a delay line interferometer (DLI) multiplexer (MUX) includes a first stage and a second stage. The first stage includes a first DLI and a second DLI. The first DLI includes a first left input, a first right input, and a first output and has a free spectral range (FSR) that is about four times a nominal channel spacing. The second DLI includes a second left input, a second right input, and a second output and has an FSR that is about four times the nominal channel spacing. The second stage is coupled to the first stage and includes a third DLI. The third DLI includes a third left input optically coupled to the first output, a third right input optically coupled to the second output, and a third output. An FSR of the third DLI is about two times the nominal channel spacing.
    Type: Application
    Filed: May 3, 2012
    Publication date: November 8, 2012
    Applicant: FINISAR CORPORATION
    Inventors: Yasuhiro Matsui, Bernd Huebner, Charles B. Roxlo
  • Patent number: 8305585
    Abstract: Apparatus and method for detecting the presence or amount or rate of binding of an analyte in a sample solution is disclosed. The apparatus includes an optical assembly having first and second reflecting surfaces separated by a distance “d” greater than 50 nm, where the first surface is formed by a layer of analyte-binding molecules, and a light source for directing a beam of light onto said first and second reflecting surface. A detector in the apparatus operates to detect a change in the thickness of the first reflecting layer resulting from binding of analyte to the analyte-binding molecules, when the assembly is placed in the solution of analyte, by detecting a shift in phase of light waves reflected from the first and second surfaces.
    Type: Grant
    Filed: May 28, 2010
    Date of Patent: November 6, 2012
    Assignee: Pall Corporation
    Inventors: Hong Tan, Yushan Tan, Duan Jun Chen, Krista Leah Witte
  • Patent number: 8264692
    Abstract: Two optical wavelengths are used to interrogate a fiber optic Fabry-Perot sensor having a moveable diaphragm that changes the width of a gap between two reflective surfaces. By picking the right operating point for the gap, the power output for one wavelength increases as the gap width changes and the power for the other wavelength decreases. A ratio of the difference of the two powers over the sum of the two powers is formed to generate a detected signal independent of power and phase fluctuations in a fiber between signal sources and sensor and between sensor and detector. This ratio, which is called the visibility, has a response proportional to the pressure of acoustic disturbances that move the diaphragm. The push-pull sensor can be used with both TDM and CW fan-out array architectures.
    Type: Grant
    Filed: July 9, 2009
    Date of Patent: September 11, 2012
    Assignee: Northrop Grumman Guidance and Electronics Company, Inc.
    Inventor: David B. Hall
  • Publication number: 20120218556
    Abstract: An apparatus for detecting a presence of one or more analytes in a sample. A plurality of optical cantilevered waveguides (200a, 200b) are optically coupled to an optical circuit between an input and an output of the circuit. Each of the optical cantilevered waveguides (200a, 200b) have an analyte selective coating, at least two of the waveguides having different analyte selective coatings. A detection module (304) analyses the output of the circuit to detect the presence of analytes in the sample.
    Type: Application
    Filed: February 25, 2011
    Publication date: August 30, 2012
    Applicant: University of Western Australia
    Inventors: John Marcel Dell, Mariusz Martyniuk, Adrian John Keating, Gino Michael Putrino, Lorenzo Faraone
  • Patent number: 8208767
    Abstract: An apparatus for estimating a parameter at distributed locations, the apparatus including: an optical fiber having: a first series of fiber Bragg gratings (FBGs) and configured to measure the parameter at a portion of the distributed locations; a second series of FBGs and configured to measure the parameter at another portion of the distributed locations; and an optical interrogator configured to illuminate the optical fiber and to receive light signals resulting from the illumination, the light signals including first light signals from the first series of FBGs within a first range of wavelengths, second light signals from the second series of FBGs within a second range of wavelengths, and other light signals within a third range of wavelengths, the ranges of wavelengths being distinct from each other; wherein the first light signals and the second light signals are used to estimate the parameter at the distributed locations.
    Type: Grant
    Filed: November 10, 2009
    Date of Patent: June 26, 2012
    Assignee: Baker Hughes Incorporated
    Inventors: Roger G. Duncan, Brooks A. Childers, Robert M. Harman
  • Patent number: 8189200
    Abstract: An apparatus and a method for multiplexing and demultiplexing Fiber Optic Interferometric Sensors (FOISs), including means for forming an optical source, at least one sensing cable, at least one wavelength demultiplexing system, and a calibration system.
    Type: Grant
    Filed: June 2, 2009
    Date of Patent: May 29, 2012
    Assignee: Sercel
    Inventors: Sylvie Menezo, Isabelle Sellin
  • Patent number: 8045174
    Abstract: A network is assessed, in particular, a network having a main line and a plurality of branch lines. The method includes the steps of: (i) introducing test signals into the main line, the main line being coupled to the branch lines; (ii) imposing a modulation on test signals which propagate along the branch line, and (iii) monitoring test signals returned along the main line. The imposed phase modulation is detected interferometrically such that the test signals from the designated branch line can be distinguished with respect to the signals returned from other branch lines.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: October 25, 2011
    Assignee: British Telecommunications Public Limited Company
    Inventors: Edmund S R Sikora, Peter Healey
  • Patent number: 8038304
    Abstract: A projector system is provided with at least one projector mobile in a specified space and adapted to project a video to a projection area included in the specified space in accordance with inputted video information, a plurality of position sensors each including a position detecting section for detecting a positional relationship of the projector with the projection area and arranged in a specified positional relationship with the specified space, and a controller for controlling a video to be projected from the projector to the projection area based on detection results by the position detecting sections of the plurality of position sensors.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: October 18, 2011
    Assignee: Panasonic Corporation
    Inventors: Kiminori Mizuuchi, Kazuhisa Yamamoto
  • Patent number: 7995209
    Abstract: An optical sensor array includes a plurality of interferometric sensors that are disposed at a plurality of locations in a region of interest. To determine a physical parameter at the plurality of locations, the array is interrogated with a plurality of optical pulses covering a range of optical wavelengths. The signals returned in response to the interrogating pulses are analyzed to determine an optical path imbalance associated with each sensor, where the optical path imbalance bears a relationship to the physical parameter of interest. Each sensor's contribution to the returned signals is determined by measuring the transit time between the launching of the interrogating pulses and the detection of the returned signals. By determining each sensor's contribution, the physical parameter may be determined at each of the plurality of locations.
    Type: Grant
    Filed: October 6, 2008
    Date of Patent: August 9, 2011
    Assignee: Schlumberger Technology Corporation
    Inventor: Arthur H. Hartog
  • Patent number: 7952717
    Abstract: A temperature measuring apparatus includes a light source, a first splitter, a second splitter, a reference beam reflector, an optical path length adjuster, a reference beam transmitting member, a first to an nth measuring beam transmitting member and a photodetector. The temperature measuring apparatus further includes a controller that stores, as initial peak position data, positions of interference peaks respectively measured in advance by irradiating the first to the nth measuring beam onto the first to the nth measurement point of the temperature measurement object, and compares the initial peak position data to positions of interference peaks respectively measured during a temperature measurement to thereby estimate a temperature at each of the first to the nth measurement point.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: May 31, 2011
    Assignee: Tokyo Electron Limited
    Inventors: Jun Abe, Tatsuo Matsudo, Chishio Koshimizu
  • Publication number: 20110122417
    Abstract: A sensor is used to measure a physical quantity and includes at least: a measurement optical fiber including at least one Bragg grating; optical means designed to inject, into the fiber, a first, “pump” wave at a first optical frequency and a second, “probe” wave at a second optical frequency, the second optical frequency being different from the first optical frequency, the Bragg grating being designed to reflect the first and second optical waves, and the optical power of the first wave being sufficient to give, after interaction with the second wave reflected by stimulated Brillouin scattering, a “Stokes” wave, the frequency of which is representative of the physical quantity to be measured; and means for analyzing the difference in frequency between the two, “pump” and “Stokes”, optical waves. The sensor may notably be used as a hydrophone.
    Type: Application
    Filed: June 25, 2009
    Publication date: May 26, 2011
    Applicant: THALES
    Inventors: Stéphanie Molin, Daniel Dolfi, Jean-Pierre Huignard, Jean-Paul Pocholle, Martine Doisy
  • Patent number: 7920270
    Abstract: An apparatus for interferometric sensing, comprising a plurality of single-longitudinal mode laser sources to each provide radiation at a corresponding plurality of selected wavelengths, and at least one modulator to frequency or phase modulate the radiation from each laser; a plurality of Fabry-Perot interferometers formed by Bragg Gratings written into optical fibre, each interferometer being responsive to one of the said plurality of wavelengths to each produce a reflected or transmitted optical output signal dependent on the corresponding interferometer path length; and one or more demodulators to demodulate the optical output signals and produce a corresponding plurality of measurement signals indicative of optical path lengths of the respective interferometers.
    Type: Grant
    Filed: October 18, 2006
    Date of Patent: April 5, 2011
    Assignee: The Australian National University
    Inventors: Jong H. Chow, Malcolm B. Gray, David E. McClelland
  • Patent number: 7864330
    Abstract: It is an object of the present invention to provide a method and a device for automatically calibrating a light intensity measurement device. The device (1) includes an optical switch (3) for switching a route of output from an optical intensity modulator (2), an optical attenuator (5) arranged on a first waveguide (4), a second waveguide (6), a light intensity measurement device (7), a control device (8) for receiving light intensity information measured by the light intensity measurement device (7) and controlling the signal to be applied to the optical intensity modulator (2), and a signal source (9) for receiving a control signal of the control device (8) and adjusting the signal to be applied to the optical intensity modulator (2).
    Type: Grant
    Filed: November 24, 2006
    Date of Patent: January 4, 2011
    Assignee: National Institute of Information and Communications Technology
    Inventors: Tetsuya Kawanishi, Masayuki Izutsu, Takahide Sakamoto, Masahiro Tsuchiya
  • Patent number: 7864329
    Abstract: A method and apparatus for detecting seismic vibrations using a series of MEMS units, with each MEMS unit including an interferometer is described. The interferometers on the MEMS units receive and modulate light from two differing wavelengths by way of a multiplexing scheme involving the use of Bragg gratings and light circulators, and an optoelectronic processor receives and processes the modulated light to discern vibrational movement of the system, which in turn allows for monitoring and calculation of a specified environmental parameter, such as seismic activity, temperature or pressure.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: January 4, 2011
    Assignee: Halliburton Energy Services, Inc.
    Inventor: John W. Berthold
  • Publication number: 20100302549
    Abstract: The invention deals with an apparatus and a method for multiplexing and demultiplexing Fiber Optic Interferometric Sensors (FOISs), said apparatus comprising: means (1) forming an optical source for providing l×n distinct trio (?qj, Fj, ?j) for the interferometric interrogation of l×n×m sensors, where for 1?j?p: ?qj is the frequency of the optical source 4qj (1?q?n/p), Fj is a RF frequency carrier generated upon the lights of the n/p emitters emitting at the frequency ?qj (1?q?n/p), and ?j is a time window where the light of the n/p emitters 4qj (1?q?n/p) are on, at least one sensing cable (100) comprising n groups of m fiber optic interferometric sensors each, and means for dedicating a unique given trio (?qj, Fj, ?j) to the interrogation of a unique group of m fiber optic interferometric sensors; at least one wavelength demultiplexing system (40) for separating the n frequencies ?qj (1?q?n/p and 1?j?p) into n/p outputs (33q for 1?q?n/p) containing respectively the lights of wavelength bands Bq for 1?q?n/
    Type: Application
    Filed: June 2, 2009
    Publication date: December 2, 2010
    Inventors: Sylvie Menezo, Isabelle Sellin
  • Patent number: 7773231
    Abstract: A differential pressure measuring system includes a light source for emitting a light, a first transducer for attenuating the intensity of the emitted light in a first range, depending on a first pressure, and providing a first light, a second transducer for attenuating the intensity of the first light in a second range, depending on a second pressure, and providing a second light, a feedback circuit for adjusting the intensity of the emitted light to maintain the intensity of the second light in the second range constant, and a measuring module for measuring a differential pressure between the first and second pressures, based on the intensities of the second light in the first and second ranges.
    Type: Grant
    Filed: August 11, 2009
    Date of Patent: August 10, 2010
    Assignee: Yamatake Corporation
    Inventor: Seiichiro Kinugasa
  • Patent number: 7728982
    Abstract: Apparatus and method for detecting the presence or amount or rate of binding of an analyte in a sample solution is disclosed. The apparatus includes an optical assembly having first and second reflecting surfaces separated by a distance “d” greater than 50 nm, where the first surface is formed by a layer of analyte-binding molecules, and a light source for directing a beam of light onto said first and second reflecting surface. A detector in the apparatus operates to detect a change in the thickness of the first reflecting layer resulting from binding of analyte to the analyte-binding molecules, when the assembly is placed in the solution of analyte, by detecting a shift in phase of light waves reflected from the first and second surfaces.
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: June 1, 2010
    Assignee: ForteBio, Inc.
    Inventors: Hong Tan, Yushan Tan, Duan Jun Chen, Krista Leah Witte
  • Patent number: 7728960
    Abstract: The invention relates to a spectroscopic arrangement and a method for combining devices for measuring material concentrations NIR associated with a spectroscopic evaluation of glass fiber and fitted with fibers Bragg gratings (FBG) for measuring temperature profiles.
    Type: Grant
    Filed: January 17, 2006
    Date of Patent: June 1, 2010
    Assignee: Bayer Technology Services GmbH
    Inventor: Wolfgang Borchers
  • Patent number: 7697121
    Abstract: The sensing system includes a plurality of modulators that are each configured to modulate a different light signal. The sensing system also includes optical pathways that transport the modulated light signals to one or more wavelength reflectors. Each wavelength reflector is configured to reflect a portion of the modulated light signals at a characteristic wavelength that is a function of an influence external to the wavelength reflector. The sensing system also includes a light sensor configured to receive the reflected light signals and to output a modulated electrical signal that is a function of the power of each of the reflected light signals. The sensing system can also include electronics configured to employ the modulated electrical signal so as to determine one or more results selected from a group consisting of: the characteristic wavelength of one or more of the wavelength reflectors and a level of the external influence on one or more of the wavelength reflectors.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: April 13, 2010
    Assignee: Kotura, Inc.
    Inventors: Trenton Gary Coroy, Bernard Thomas Smith
  • Patent number: 7697797
    Abstract: The present invention is a diaphragm-fiber optic sensor (DFOS), interferometric sensor. This DFOS is based on the principles of Fabry-Perot and Michelson/Mach-Zehnder. The sensor is low cost and is designed with high efficiency, reliability, and Q-point stability, fabricated using MEMS (micro mechanic-electrical system) technology, and has demonstrated excellent performance. A DFOS according to the invention includes a cavity between two surfaces: a diaphragm made of silicon or other material with a rigid body (or boss) at the center and clamped along its edge, and the endface of a single mode optic fiber. By utilizing MEMS technology, the gap width between the diaphragm and the fiber endface is made accurately, ranging from 1 micron to 10 microns.
    Type: Grant
    Filed: September 25, 2008
    Date of Patent: April 13, 2010
    Assignee: New Jersey Institute of Technology
    Inventors: Ken K Chin, Guanhua Feng, Ivan Padron, Harry Roman
  • Publication number: 20100085572
    Abstract: An optical sensor array includes a plurality of interferometric sensors that are disposed at a plurality of locations in a region of interest. To determine a physical parameter at the plurality of locations, the array is interrogated with a plurality of optical pulses covering a range of optical wavelengths. The signals returned in response to the interrogating pulses are analyzed to determine an optical path imbalance associated with each sensor, where the optical path imbalance bears a relationship to the physical parameter of interest. Each sensor's contribution to the returned signals is determined by measuring the transit time between the launching of the interrogating pulses and the detection of the returned signals. By determining each sensor's contribution, the physical parameter may be determined at each of the plurality of locations.
    Type: Application
    Filed: October 6, 2008
    Publication date: April 8, 2010
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventor: Arthur H. Hartog
  • Publication number: 20100046002
    Abstract: A plurality of Fabry-Perot interferometric sensors are optically coupled in series with each other to form an ordered optical series. Each Fabry-Perot interferometric sensor has a unique signalband and a passband. Each Fabry-Perot interferometric sensor has its unique signalband within the passbands of all of the next higher ordered Fabry-Perot interferometric sensors in the optical series so that a corresponding unique fringe signal from each of the Fabry-Perot interferometric sensors is a multiplexed output from the optical series.
    Type: Application
    Filed: August 21, 2009
    Publication date: February 25, 2010
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Maximillian A. Perez, Andrei A. Shkel
  • Publication number: 20100039650
    Abstract: The subject of the present invention is a dynamic sensor of physical quantities with optical waveguide with optically-pumped amplifier medium, which requires no interferometer or reference sensor and which makes it possible to obtain at least the same level of performance, in terms of sensitivity, as known sensors of this type, and this waveguide is linked at one end to a selective mirror, and comprises at its other end an interrogation laser, the reflection of which on the selective mirror produces a wave which, by interference with the incident wave, provokes the periodic saturation of the gain of the waveguide.
    Type: Application
    Filed: February 27, 2008
    Publication date: February 18, 2010
    Applicant: Thales
    Inventors: Stephanie Molin, Daniel Dolfi, Jean-Pierre Huignard, Martine Doisy
  • Patent number: 7656536
    Abstract: Apparatus and method for detecting an analyte in a sample based on optical interference. The apparatus includes a light source, detector unit and one or more disposable detector tips. The apparatus also includes an optical coupling assembly that couples light from the source to the detector tips, and from the detector tips to the detector unit.
    Type: Grant
    Filed: December 14, 2007
    Date of Patent: February 2, 2010
    Assignee: Fortebio, Inc.
    Inventors: Hong Tan, Yushan Tan, Krista Leah Witte, Greg L. Carricato, Scott Lockard
  • Patent number: 7623245
    Abstract: A differential pressure measuring system includes a light source for emitting a light, a first transducer for attenuating the intensity of the emitted light in a first range, depending on a first pressure, and providing a first light, a second transducer for attenuating the intensity of the first light in a second range, depending on a second pressure, and providing a second light, a feedback circuit for adjusting the intensity of the emitted light to maintain the intensity of the second light in the second range constant, and a measuring module for measuring a differential pressure between the first and second pressures, based on the intensities of the second light in the first and second ranges.
    Type: Grant
    Filed: October 2, 2006
    Date of Patent: November 24, 2009
    Assignee: Yamatake Corporation
    Inventor: Seiichiro Kinugasa
  • Publication number: 20090279098
    Abstract: An optical coherence tomography apparatus constructs a tomographic image of a measurement object on the basis of a spectral characteristic obtained by spectrally dividing interference light, which combines signal light composed of the measurement light reflected by the measurement object and reference light, using an optical demultiplexer.
    Type: Application
    Filed: July 14, 2009
    Publication date: November 12, 2009
    Applicant: SCHOOL JURIDICAL PERSON KITASATO INSTITUTE
    Inventors: Kohji Ohbayashi, Kimiya Shimizu
  • Patent number: 7616321
    Abstract: An optical coupler for coupling to a rotating catheter has a housing with a rotatable distal face and a stationary proximal face. The distal face has an eccentric port and a central port. A lens is disposed inside the housing to intercept a rotating collection beam emerging from the eccentric port and to re-direct the collection beam to a focus proximal to the lens as the collection beam rotates. A beam re-director disposed between the lens and the distal face is oriented to direct a delivery beam toward the central port.
    Type: Grant
    Filed: July 8, 2003
    Date of Patent: November 10, 2009
    Assignee: InfraReDx, Inc.
    Inventor: Jeff Korn
  • Patent number: 7589312
    Abstract: A physical quantity measuring system includes an optical fiber in which plural fiber Bragg gratings having different reflection wavelength changing bands are formed along the optical fiber in a longitudinal direction, a light source which outputs a broadband light into the optical fiber, an arrayed waveguide grating and an operating portion. The arrayed waveguide grating divides a light reflected by the fiber Bragg grating and outputted from the optical fiber into plural divisional wavelength bands. The arrayed waveguide grating outputs the divided lights to output channels. The operating portion detects a change of a reflected center wavelength of each fiber Bragg grating by a change of an output of each light-receiving element, operates a physical quantity and a position thereof given to the optical fiber, and is capable of detecting light from adjacent output channels.
    Type: Grant
    Filed: December 3, 2007
    Date of Patent: September 15, 2009
    Assignee: Hitachi Cable, Ltd.
    Inventor: Seiji Kojima
  • Patent number: 7576864
    Abstract: An interferometric measuring device for recording geometric data for surfaces of at least one object, including a beam supply section including a modulation interferometer fed by a light source including temporarily coherent broadband radiation, a measuring interferometer system that is connected thereto and includes a plurality of probe units for emitting radiation of measuring beams onto the assigned surface locations and recording the radiation reflected by the surface locations, the radiation forming interference with radiation reflected by a related reference element system, and including a downstream receiving and evaluation device for determining geometric data on the basis of the interfering radiation.
    Type: Grant
    Filed: August 17, 2004
    Date of Patent: August 18, 2009
    Assignee: Robert Bosch GmbH
    Inventors: Michael Lindner, Bernd Schmidtke
  • Patent number: 7548319
    Abstract: A method of measuring a selected physical parameter at a location within a region of interest comprises the steps of: launching optical pulses at a plurality of preselected interrogation wavelengths into an optical fiber (1) deployed along the region of interest, reflectors (20, 21, 2n) being arrayed along the optical fiber (1) to form an array (9) of sensor elements, the optical path length between the said reflectors (2) being dependent upon the selected parameter; detecting the returned optical interference signal for each of the preselected wavelengths; determining from the optical interference signal the absolute optical path length (L) between two reflectors (2) at the said location; and determining from the absolute optical path length (L) the value of the selected parameter at the said location; wherein the step of determining the absolute optical path length (L) comprises carrying out a process in which the phase difference between the interference signals for a pair of the preselected wavelengths is
    Type: Grant
    Filed: January 20, 2004
    Date of Patent: June 16, 2009
    Assignee: Sensor Highway Limited
    Inventor: Arthur H. Hartog
  • Patent number: 7538860
    Abstract: A system and method for determining a reflection wavelength of multiple Bragg gratings in a sensing optical fiber comprise: (1) a source laser; (2) an optical detector configured to detect a reflected signal from the sensing optical fiber; (3) a plurality of frequency generators configured to generate a signal having a frequency corresponding to an interferometer frequency of a different one of the plurality of Bragg gratings; (4) a plurality of demodulation elements, each demodulation element configured to combine the signal produced by a different one of the plurality of frequency generators with the detected signal from the sensing optical fiber; (5) a plurality of peak detectors, each peak detector configured to detect a peak of the combined signal from a different one of the demodulation elements; and (6) a laser wavenumber detection element configured to determine a wavenumber of the laser when any of the peak detectors detects a peak.
    Type: Grant
    Filed: August 17, 2007
    Date of Patent: May 26, 2009
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Jason P. Moore
  • Patent number: 7505642
    Abstract: A sensor device that uses a number of bragg grating (FBG) sensors and novel interrogation system with a ring cavity configuration for simultaneous time-division-multiplexex (TDM) and wavelength-division-multiplexed (WDM) interrogation of FBG sensors. The ring cavity includes an amplifier, and output coupler and an optical circulator. The coupler is connected to a wavelength measuring system and the optical circulator is connected to the FBG sensors. The FBG sensors can be in a number of groups. TDM interrogation is applied to each group of FBG sensors while WDM interrogation is applied to each FBG sensors within each group.
    Type: Grant
    Filed: July 23, 2007
    Date of Patent: March 17, 2009
    Assignee: The Hong Kong Polytechnic University
    Inventors: Hwa Yaw Tam, Weng Hong Chung
  • Patent number: 7502120
    Abstract: The invention relates to an apparatus for multiplexing Fiber Optic Interferometric Sensors (FOISs), which apparatus comprises means (1) forming the an optical source for providing m*n distinct wavelengths ?11, ?12, . . . , ?1n, ?21, ?22, . . . , ?2n, . . . , ?m1, ?m2, . . . , ?mn, the optical source including means for generating m groups (111, 112, . . . , 11m) of light pulses, each group 11j (1?j?m) being made up of n light pulses Pk(?j1), Pk(?j2), . . . , Pk(?jn) of distinct wavelengths ?j1, ?j2, . . . , ?jn, the n light pulses Pk(?j1), Pk(?j2), . . . , Pk(?jn) being time delayed one from another, Fiber Optic Interferometric Sensors distributed in m groups (51, 52, . . .
    Type: Grant
    Filed: December 13, 2005
    Date of Patent: March 10, 2009
    Assignee: Sercel
    Inventor: Sylvie Menezo
  • Patent number: 7499738
    Abstract: Assembly and method for measuring the concentration of an analyte in a biological matrix. The assembly includes an implantable optical-sensing element that comprises a body, and a membrane mounted on the body in a manner such that the membrane and the body define a cavity. The membrane is permeable to the analyte, but is impermeable to background species in the biological matrix. A refractive element is positioned in the cavity. A light source transmits light of a first intensity onto the refractive element, and a light detector receives light of a second intensity that is reflected from the cavity. A controller device optically coupled to the detector compares the first and second light intensities, and relates the intensities to analyte concentration.
    Type: Grant
    Filed: April 27, 2005
    Date of Patent: March 3, 2009
    Assignee: Roche Diagnostics Operations, Inc.
    Inventors: Martin Gerber, Matthias Essenpreis, Wolfgang Petrich
  • Patent number: 7480056
    Abstract: A method for interrogating time-multiplexed interferometric sensors using multiple interrogation pulses so as to increases the allowable interrogation pulse duty-cycle and improve the signal-to-noise ratio. In each TDM repetition period a sequence of multiple interrogation pulses are generated. The pulses in the sequence are separated by a time that is equal to the sensor imbalance. The phase from pulse to pulse in each TDM time-slot is modulated at a different, linear rate such that the pulse in time-slot m will have an optical frequency that is shifted by m??, where ?? is the sub-carrier frequency. Because multiple reflections do not need to fade out the inventive method can enhance the signal-to-noise ratio of interferometric sensors such as inline Fabry-Perot sensors.
    Type: Grant
    Filed: June 4, 2004
    Date of Patent: January 20, 2009
    Assignee: Optoplan AS
    Inventors: Ole Henrik Waagaard, Erlend Ronnekleiv
  • Publication number: 20080309945
    Abstract: A physical quantity measuring system according to the present invention comprises: an optical fiber having fiber Bragg gratings; a light source connected to the optical fiber; an arrayed waveguide grating connected between the light source and the optical fiber via an optical branching filter, and having output channels of which central wavelengths of at least three output channels are included in a one-tenth loss band of a reflected light by the fiber Bragg grating; light receiving devices for receiving light output from the output channels on a one-to-one basis; and a central reflected wavelength change detecting unit connected to the light receiving devices for estimating a change in a central reflected wavelength based on a physical quantity, by calculating first and second group signals from light receiving signals corresponding to the at least three output channels, and by calculating a differential signal between the first and the second group signals.
    Type: Application
    Filed: March 18, 2008
    Publication date: December 18, 2008
    Inventors: Seiji KOJIMA, Shinji KOMATSUZALI
  • Patent number: 7466422
    Abstract: Unwanted signal components in time-division multiplexed (TDM) systems may lead to crosstalk and noise if these pulses overlap with signal pulses from an interrogated sensor. The crosstalk and noise are dominated by interference between the signal pulses from the interrogated sensor and the unwanted signal components and can be greatly reduced by suppressing this interference signal. The unwanted signal components may include overlapping pulses originating from different sets of interrogation pulses (repetition periods). Modulating the phase or frequency between the repetition periods so that the unwanted interference signal does not appear at frequencies from which the phase of the interrogated sensor is demodulated suppresses this interference. Other unwanted signal components include leakage light during dark periods of the duty cycle of an interrogation signal.
    Type: Grant
    Filed: October 2, 2007
    Date of Patent: December 16, 2008
    Assignee: Optoplan AS
    Inventors: Ole Henrik Waagaard, Erlend Rønnekleiv
  • Publication number: 20080291461
    Abstract: Unwanted signal components in time-division multiplexed (TDM) systems may lead to crosstalk and noise if these pulses overlap with signal pulses from an interrogated sensor. The crosstalk and noise are dominated by interference between the signal pulses from the interrogated sensor and the unwanted signal components and can be greatly reduced by suppressing this interference signal. The unwanted signal components may include overlapping pulses originating from different sets of interrogation pulses (repetition periods). Modulating the phase or frequency between the repetition periods so that the unwanted interference signal does not appear at frequencies from which the phase of the interrogated sensor is demodulated suppresses this interference. Other unwanted signal components include leakage light during dark periods of the duty cycle of an interrogation signal.
    Type: Application
    Filed: August 7, 2008
    Publication date: November 27, 2008
    Inventors: OLE HENRIK WAAGAARD, Erlend Ronnekleiv
  • Publication number: 20080291460
    Abstract: A method for detecting and measuring physical perturbations sensed by a multi-mode waveguide, through which a number of modes of a coherent electromagnetic wave propagates through and exit from. The method comprises irradiating the exiting electromagnetic wave on one or more two-dimensional sensing arrays comprising a plurality of sensing elements that are sensitive to the irradiated electromagnetic wave; determining, simultaneously, in a parallel manner, absolute values of sensed changes across different zones of the two-dimensional sensing arrays, each zone comprising one or more sensing elements; and summing the absolute values of different groups of different zones to obtain a representation of the perturbations.
    Type: Application
    Filed: December 28, 2005
    Publication date: November 27, 2008
    Inventors: Arkady Khatchaturov, Uri Voitsechov, Avram Matcovitch