Multiplexed Sensor Array Patents (Class 356/478)
  • Patent number: 10429542
    Abstract: A method for estimating an environmental parameter includes transmitting a first interrogation signal into an optical fiber, receiving a reflected return signal including light reflected from one or more of the plurality of FBG's in the fiber and receiving at a processor data describing the reflected return signal. The received data is comparted to expected data to determine a shift in wavelength of light reflected for one or more of the plurality of FBGs and a change in a length of a dead zone of the optical fiber based on the comparison is also determined. From this, estimates of locations two or more of the plurality of FBG's are formed.
    Type: Grant
    Filed: December 23, 2013
    Date of Patent: October 1, 2019
    Assignee: BAKER HUGHES, A GE COMPANY, LLC
    Inventors: Brooks A Childers, Christopher J Fazio, Roger Glen Duncan
  • Patent number: 10422623
    Abstract: A photonic integrated circuit wavelength tunable laser device includes a gain element integrated into a photonic integrated circuit. The gain element provides optical gain to an optical signal. A tunable filter is integrated into the photonic integrated circuit. A modulator is integrated into the photonic integrated circuit that modulates the optical signal as a function of time, wherein the gain element, the tunable filter, and the modulator form a wavelength tunable laser device having a wavelength that tunes as a function of time.
    Type: Grant
    Filed: September 27, 2017
    Date of Patent: September 24, 2019
    Inventor: Eric Swanson
  • Patent number: 10281397
    Abstract: An optical sensor and corresponding method of operation can detect a phase transition and/or related property of a hydrocarbon-based analyte. The optical sensor includes an optical element with a metallic film coupled or integral thereto, with a sample chamber holds the hydrocarbon-based analyte such that the hydrocarbon-based analyte is disposed adjacent the metallic layer. The optical sensor further includes a light source configured to direct light through the optical element such that the light is reflected by the metallic layer under conditions of surface plasmon resonance. The optical sensor analyzes the reflected light to detect a phase transition and/or related property of a hydrocarbon-based analyte.
    Type: Grant
    Filed: November 10, 2016
    Date of Patent: May 7, 2019
    Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Vincent Joseph Sieben, Kenneth John Chau, Shahnawaz Hossain Molla, Cailan Libby, Mohammed Al-Shakhs, Farshid Mostowfi, Simon Ivar Andersen, Elizabeth Jennings Smythe
  • Patent number: 10247581
    Abstract: The invention relates to a method of interrogating an interferometric optical fiber sensor system including a laser source configured to generate interrogation light and a sensor array with at least a first reflector and a second reflector.
    Type: Grant
    Filed: April 28, 2015
    Date of Patent: April 2, 2019
    Assignee: Optoplan AS
    Inventors: Erlend Ronnekleiv, Ole Henrik Waagaard
  • Patent number: 10190926
    Abstract: A Fiber Bragg grating (FBG) sensor structure, a method of fabricating a FBG sensor structure, and a method of employing a FBG sensor structure comprising an optical fiber portion having at least one FBG formed therein. The FBG sensor structure comprises an optical fiber portion having at least one FBG formed therein; and a sleeve structure capable of transferring vibrations and/or strain along a length thereof; wherein the optical fiber portion is coupled to the sleeve structure such that the central wavelength of the FBG, is variable under the transferred vibrations and/or strain.
    Type: Grant
    Filed: April 11, 2016
    Date of Patent: January 29, 2019
    Assignees: AGENCY FOR SCIENCE, TECHNOLOGY AND RESEARCH, ST ELECTRONICS (SATCOM & SENSOR SYSTEMS) PTE LTD
    Inventors: Jianzhong Hao, Bo Dong, Verghese Paulose, Bo Lin, Peng Peng Bernard Lee, Boon Hock Tan
  • Patent number: 10088353
    Abstract: A distributed fiber optic cable comprises an elongate body and a first optical fiber longitudinally housed in the body, wherein the fiber describes a sinusoid having an amplitude and a first wavelength along the length of the body and wherein the sinusoid rotates along the length of the body so as to describe a twisted sinusoid having a twist wavelength. A method for sensing an acoustic wave comprises a) providing a set of signals collected from the cable, b) processing the signals so as to divide the fiber in each twist wavelength of cable into a predetermined number of channels, c) measuring the amplitudes in each channel and calculating the maximum and minimum amplitude in a preselected length of cable, d) using the calculated maximum and minimum for the preselected length of cable to determine the amplitude and direction of the wave at the preselected length of cable.
    Type: Grant
    Filed: July 30, 2013
    Date of Patent: October 2, 2018
    Assignee: SHELL OIL COMPANY
    Inventors: Boris Nikolaevich Kuvshinov, Johan Cornelis Hornman
  • Patent number: 10082425
    Abstract: A confocal chromatic device is provided, including at least one chromatic lens with an extended axial chromatism; at least one broadband light source; at least one optical detector; and at least one measurement channel with a planar Y-junction made with a planar waveguide optics technology, and arranged for transferring light from the at least one light source towards the at least one chromatic lens and for transferring light reflected back through the at least one chromatic lens towards the at least one optical detector.
    Type: Grant
    Filed: September 30, 2016
    Date of Patent: September 25, 2018
    Assignee: UNITY SEMICONDUCTOR
    Inventor: Philippe Gastaldo
  • Patent number: 9926778
    Abstract: Method and apparatus are disclosed for use of a fiber-optic sensor loop for use within a wellbore; with a plurality of light sources optically coupled to the fiber-optic sensor loop; at least one electromagnetically sensitized region within the fiber-optic sensor loop; and a plurality of detectors optically coupled to the fiber-optic sensor loop; and using the sensing system to detect changes in a magnetic field within the wellbore.
    Type: Grant
    Filed: December 20, 2013
    Date of Patent: March 27, 2018
    Assignee: Halliburton Energy Services, Inc.
    Inventors: John L. Maida, Tasneem A. Mandviwala, Allen Cekorich
  • Patent number: 9909903
    Abstract: The application describes methods and apparatus for distributed fiber sensing, especially distributed acoustic/strain sensing. The method involves launching at least first and second pulse pairs into an optical fiber, the first and second pulse pairs having the same frequency configuration as one another and being generated such that the phase relationship of the pulses of the first pulse pair has a predetermined relative phase difference to the phase relationship of the pulses of the second pulse pair. In one embodiment there is a frequency difference between the pulses in a pulse pair which is related to the launch rate of the pulse pairs. In another embodiment the phase difference between the pulses in a pair is varied between successive launches. In this way an analytic version of the backscatter interference signal can be generated within the baseband of the sensor.
    Type: Grant
    Filed: April 6, 2012
    Date of Patent: March 6, 2018
    Assignee: Optasense Holdings Ltd.
    Inventors: Andrew Biggerstaff Lewis, Stuart John Russell
  • Patent number: 9823060
    Abstract: The invention relates to a system (1) comprising a deformable surface (2) and a first and a second sensor (C1, C2) designed to provide a first and a second measurement signal (S1, S2) intended to be collected by a processing circuit (12), said system (1) comprising first and second measurement paths (V1, V2) for collecting the first and second measurement signals (S1, S2), said system (1) being characterized in that it comprises a common calibration member (20) for simultaneously injecting into the first and second measurement paths (V1, V2) a calibration signal (SE), said common calibration member (20) being designed so that the image signals (S?1, S?2, S?n) restored via said measurement paths (V1, V2, Vn) are independent of said movable surface (2). Deformable movable surface systems, of the deformable mirror type.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: November 21, 2017
    Assignee: ALPAO
    Inventor: Michel Raymond Barrault
  • Patent number: 9816374
    Abstract: An example telemetry signal detection apparatus may include a optical splitter, a light source optically coupled to the optical splitter, and a light detector optically coupled to the optical splitter. The apparatus further may include a reference loop optically coupled to the optical splitter and a sensor loop optically coupled to the reference loop and the optical splitter. The reference loop may be contained within a reference loop enclosure. The sensor loop and reference loop may comprise a zero-area Sagnac loop with folded optical fiber or dual fiber cable configurations.
    Type: Grant
    Filed: April 30, 2014
    Date of Patent: November 14, 2017
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Zbigniew Stanislaw Sobolewski, Douglas Mark Knight, John Laureto Maida, Neal Gregory Skinner
  • Patent number: 9810556
    Abstract: There is described a sensor apparatus. It comprises an interrogator comprising a light source emitting pulses having a wavelength about an average wavelength; and a fiber Bragg grating (FBG) arrangement. The arrangement comprises a FBG sensor array comprising a plurality of FBG sensors on an optical fiber and being for reflecting the pulses, thereby producing reflected pulses at each one of the FBG sensors. FBG sensors of a given FBG sensor array have a spatial separation therebetween which is sufficient to allow, at a receiver, a temporal discrimination between the reflected pulses produced by each one of the FBG sensors. The FBG sensor array has a spectral reflection window which comprises the average wavelength.
    Type: Grant
    Filed: April 2, 2015
    Date of Patent: November 7, 2017
    Inventor: François Ouellette
  • Patent number: 9784561
    Abstract: An optical imaging system includes an optical radiation source (410, 510), a frequency clock module outputting frequency clock signals (420), an optical interferometer (430), a data acquisition (DAQ) device (440) triggered by the frequency clock signals, and a computer (450) to perform multi-dimensional optical imaging of the samples. The frequency clock signals are processed by software or hardware to produce a record containing frequency-time relationship of the optical radiation source (410, 510) to externally clock the sampling process of the DAQ device (440). The system may employ over-sampling and various digital signal processing methods to improve image quality. The system further includes multiple stages of routers (1418, 1425) connecting the light source (1410) with a plurality of interferometers (1420a-1420n) and a DAQ system (1450) externally clocked by frequency clock signals to perform high-speed multi-channel optical imaging of samples.
    Type: Grant
    Filed: February 27, 2014
    Date of Patent: October 10, 2017
    Assignee: Thorlabs, Inc.
    Inventors: James Y. Jiang, Scott Barry, Alex E. Cable
  • Patent number: 9766371
    Abstract: A distributed optical fiber sensing system is provided. The system can include an interrogator, a transmission optical fiber, a sensing optical fiber, and a reflector. Each of the transmission optical fiber and the sensing optical fiber includes at least one circulator. The reflector is optically coupled to the transmission optical fiber for sensing separate regions along the sensing optical fiber.
    Type: Grant
    Filed: October 17, 2013
    Date of Patent: September 19, 2017
    Assignee: HALLIBURTON ENERGY SERVICES, INC.
    Inventors: David Andrew Barfoot, Michel Joseph LeBlanc, Neal Gregory Skinner
  • Patent number: 9568339
    Abstract: Methods and systems using one or more distributed feedback (DFB) lasers for capturing changes in the lasing environment are disclosed. Specifically, a sensor for measuring a measurand, such as pressure or temperature, or changes in a measurand, includes a fiber with at least one core, at least one fiber laser cavity formed by a single fiber grating in the core, wherein the laser operates on at least two modes along at least part of its length. The DFB laser includes a section that is bent into a non-linear shape and at least one pump laser connected to the fiber laser cavity. When the DFB laser experiences a perturbation or measurand change that changes the spacing of the modes, a change in an RF beat note is generated. This beat note can then be measured and related to the measurand change.
    Type: Grant
    Filed: December 2, 2011
    Date of Patent: February 14, 2017
    Assignee: OFS FITEL, LLC
    Inventors: Kazi S. Abedin, Paul S. Westbrook
  • Patent number: 9488786
    Abstract: Optical-based apparatus and method for sensing parameters in connection with an asset, such as a pipeline, are provided. At least two sites in an optical fiber may include a respective fiber grating arranged to have a respective optical response in a wavelength spectrum having a distinguishing feature indicative of a value of a respective local parameter at a respective grating site. The two fiber gratings may be further arranged to form, in combination with a respective portion of the optical fiber which extends between the two sites, respective optical backscatter portions that when combined with one another are effective to sense an optical change in the fiber portion between the sites indicative of a value of a distributed parameter. This is a parameter modality different from a parameter modality of the respective local parameters at the respective grating sites.
    Type: Grant
    Filed: November 16, 2012
    Date of Patent: November 8, 2016
    Assignee: General Electric Company
    Inventors: Glen Peter Koste, Raymond Verle Jensen, Hua Xia, Boon Kwee Lee, Victor Petrovich Ostroverkhov, Sachin Narahari Dekate, William Albert Challener
  • Patent number: 9412565
    Abstract: A temperature measuring method for measuring a temperature of a member corresponding to a measuring object arranged within a chamber of a plasma processing apparatus is provided. The temperature measuring method involves obtaining a function (f) for correcting a correction target temperature (Tmeas) according to a measurement window temperature (Tw), the function (f) being computed based on the correction target temperature (Tmeas) corresponding to a temperature of the measuring object measured via a measurement window arranged at the chamber, a reference temperature (Tobj) corresponding to a temperature of the measuring object measured without using the measurement window, and the measurement window temperature (Tw) corresponding to a temperature of the measurement window.
    Type: Grant
    Filed: January 30, 2015
    Date of Patent: August 9, 2016
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Yusuke Yoshida, Ryou Son, Takahiro Senda, Masayuki Kohno, Naoki Matsumoto
  • Patent number: 9404736
    Abstract: Deformation measurement sensor operating in a hostile environment and including an optical movement measurement module, and measurement system using said sensor. The sensor includes: an enclosure comprising an opening; a movable element having a first surface that is brought into contact with an object (4) that can deform, for example a nuclear fuel rod, and a second surface that is reflective and extends into the enclosure through the opening; a sealed, resilient connecting component performing a return function between the element and the enclosure; and, inside the enclosure, a module for creating an interference light using a light reflected by the second surface of the element. Deformation of the object results in a modification to the interference light that is representative of the deformation.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: August 2, 2016
    Assignee: Commissariat a L'Energie Atomique et aux Energies Alternatives
    Inventors: Stéphane Gaillot, Nicolas Regazzoni, Guy Cheymol
  • Patent number: 9273948
    Abstract: An input of an optical interferometer is a periodical optical pulse. A phase of a first half and a latter half of a reference pulse is a 90 degree (independently orthogonal) phase difference. Two interferometric outputs i1 and i2, where the phase difference is 90 degrees from each other, are obtained by interference of the reference pulse and the signal pulse. ? is calculated by referring the amplitude of reference pulse and the signal pulse to remove the light intensity fluctuations. Two values of cos ?1 and cos ?2 are calculated and positions are determined on the cosine curve by obtaining ?1 and ?2 values. ??1 and ??2, which are the phase increment or decrement of both ?1 and ?2 in a T period, are summed and becomes the sensor output signal that removes the measurement range limitation of ±90 degrees (a half wavelength of light) of the light phase.
    Type: Grant
    Filed: November 19, 2012
    Date of Patent: March 1, 2016
    Assignee: HAKUSAN CORPORATION
    Inventor: Kazumasa Tsukada
  • Patent number: 9257031
    Abstract: The invention relates to a method for detecting crack formation in a hoisting member, comprising the steps of measuring a stress under load at two points of the hoisting member, comparing the measured stresses and generating a warning signal when the measured stresses differ too much from each other. The invention also relates to a device for detecting crack formation in a hoisting member, comprising means arranged at two points of the hoisting member for measuring a stress under load, means connected to the measuring means for comparing the measured stresses, and means connected to the comparing means for generating a warning signal when the measured stresses differ too much from each other. Finally, the invention relates to a hoisting frame, comprising a number of hoisting members which are mounted thereon close to its corners, and crack detection devices connected thereto.
    Type: Grant
    Filed: October 17, 2011
    Date of Patent: February 9, 2016
    Assignee: STINIS BEHEER B.V.
    Inventor: Cornelis Stinis
  • Patent number: 9217629
    Abstract: A displacement sensor for sensing the displacement of a movable component of a device is provided. A flexible element of the displacement sensor includes a mounting portion mounted to the device and a coupling portion spaced apart from the mounting portion. A displacement conversion mechanism is coupled to the movable component and is further coupled to the coupling portion of the flexible element. The displacement conversion mechanism is configured to convert a larger displacement of the movable component into a smaller displacement of the coupling portion of the flexible element. The flexible element is arranged such that a displacement at the coupling portion causes the flexible element to bend.
    Type: Grant
    Filed: August 19, 2013
    Date of Patent: December 22, 2015
    Assignee: SIEMENS AKTIENGESELLSCHAFT
    Inventors: Endre Brekke, Hessam Moussavinik, Kjetil Volent
  • Patent number: 9207068
    Abstract: A displacement sensor for sensing the displacement of a movable component is provided. The displacement sensor includes a displacement transmission mechanism configured to reduce a large displacement provided at its input into a smaller displacement at its output. The displacement sensor further includes a fiber optic displacement sensor, wherein the output of the displacement transmission mechanism is coupled to the fiber optic displacement sensor.
    Type: Grant
    Filed: August 19, 2013
    Date of Patent: December 8, 2015
    Assignee: SIEMENS AKTIENGESELLSCHAFT
    Inventors: Endre Brekke, Hessam Moussavinik, Kjetil Zsolt Volent
  • Patent number: 9140643
    Abstract: A system for remotely sensing a target material in situ include a broad-band laser source, at least one tunable filter coupled to the source laser for generating a swept-frequency signal an optical device for splitting the swept-frequency signal into a first illumination signal and second illumination signal, a first optical path for directing the first illumination signal unto the target material and receiving a reflected signal from the target material, a second optical path for receiving the second illumination signal and generating a spectral reference signal, and a controller coupled to the first optical path and the second optical path for adjusting the frequency and spatial resolution of the laser source based at least in part on a comparison of the spectral reference signal and the reflected signal.
    Type: Grant
    Filed: April 11, 2012
    Date of Patent: September 22, 2015
    Assignee: CHEVRON U.S.A. INC.
    Inventors: Jerome Anthony Bellian, Christopher Michael Tolleson
  • Patent number: 9103733
    Abstract: A bearing comprises a Bragg grated optical fiber to measure one or more parameters of the bearing such as load, temperature, acceleration/vibration and identification. To be able to fit as many Bragg gratings as possible, the utilization of the corresponding frequency plane output is optimized by having low bandwidth next to large bandwidth sensors in the frequency place. The corresponding physical sensors such as load sensors on a bearing will not be adjacent. Sensors in the loaded zone are giving a high bandwidth output and sensors in the un-loaded zone are giving a low bandwidth output, thus even though these are not physically adjacent, the corresponding frequency areas are adjacent by appropriate grating.
    Type: Grant
    Filed: November 26, 2010
    Date of Patent: August 11, 2015
    Assignee: AKTIEBOLAGET SKF
    Inventor: Adam Reedman
  • Patent number: 9086331
    Abstract: The present disclosure is generally directed to a strain sensor, system and method of fabrication and use that includes an optical fiber, an optical signal generator that transmits an optical signal through the optical fiber, at least two photonic crystal slabs within the optical fiber separated by a first segment of optical fiber, a photo-detector that detects a reflected optical signal from the at least two photonic crystal slabs, and a processor that computes a mechanical strain over the first segment of optical fiber based on the reflected optical signal detected by the photo-detector.
    Type: Grant
    Filed: October 23, 2012
    Date of Patent: July 21, 2015
    Assignee: The Boeing Company
    Inventors: Michael A. Carralero, Ty Aaby Larsen, Priya Maratukulam
  • Patent number: 9055962
    Abstract: A surgical instrument that includes a housing linkable with a manipulator arm of a robotic surgical system, a shaft coupled to the housing, a force transducer on a distal end of the shaft, and a plurality of fiber optic strain gauges on the force transducer is disclosed. The plurality of strain gauges are coupled to a fiber optic splitter or an arrayed waveguide grating (AWG) multiplexer, which can be coupled to a fiber optic connector. A wrist joint coupled to an end effector is coupled to a distal end of the force transducer. A robotic surgical manipulator that includes a base link coupled to a distal end of a manipulator positioning system, and a distal link with an instrument interface, and a fiber optic connector optically linkable to a surgical instrument. A method of passing data between an instrument and a manipulator via optical connectors is also provided.
    Type: Grant
    Filed: May 10, 2013
    Date of Patent: June 16, 2015
    Assignee: INTUITIVE SURGICAL OPERATIONS, INC.
    Inventors: Stephen J. Blumenkranz, Gregory W. Dachs, II, Ian McDowall, Christopher J. Hasser
  • Publication number: 20150131103
    Abstract: A fiber optic sensing system. The fiber optic sensing includes an optical source and a lead cable for receiving an optical signal from the optical source. The fiber optic sensing system also includes a sensor array for receiving the optical signal from the lead cable. The sensor array includes a plurality of fiber optic sensors, each of the plurality of fiber optic sensors including an interferometer having two legs. The plurality of fiber optic sensors includes a noise compensation sensor. Each of the legs of the interferometer of the noise compensation sensor is configured to sense vibration in substantially the same manner.
    Type: Application
    Filed: August 14, 2013
    Publication date: May 14, 2015
    Applicant: US Seismic Systems, Inc.
    Inventors: Eric L. Goldner, Gerald Robert Baker
  • Patent number: 9025158
    Abstract: An interferometric measurement system suppresses cross talk between optical waveguides used to measure one or more parameters. A first interferometric measurement channel coupled to a first waveguide, and a second interferometric measurement channel coupled to a second waveguide. At least one of the channels includes a reference light path in addition to the first and second waveguides. A reference path optical delay is associated with the reference light path, a first optical delay is associated with the input portion of at least one of the first and second interferometric measurement channels, and a second optical delay is associated with an output portion of the one interferometric measurement channel. A value of the first optical delay and a value the second optical delay are chosen to suppress crosstalk associated with the other of the first and second interferometric measurement channels in the one interferometric measurement channel over a predetermined length of the first waveguide.
    Type: Grant
    Filed: May 23, 2011
    Date of Patent: May 5, 2015
    Assignee: Intuitive Surgical Operations, Inc.
    Inventors: Mark E. Froggatt, Justin W. Klein
  • Patent number: 8994953
    Abstract: Interrogation of a phase based transducer is performed by temporally overlapping and interfering a single pulse output from the transducer to determine the rate of change with time of the measurand represented as a phase change. The rate of change, or derivative of the phase change typically has a much smaller amplitude than the signal itself, and the derivative measurement therefore has reduced sensitivity. In this way, large amplitude signals which might otherwise be subject to overscaling effects can be measured more effectively.
    Type: Grant
    Filed: August 20, 2009
    Date of Patent: March 31, 2015
    Assignee: Qinetiq Limited
    Inventor: Roger Ian Crickmore
  • Patent number: 8983287
    Abstract: A personnel monitoring system. The personnel monitoring system includes a host node having an optical source for generating optical signals, and an optical receiver. The personnel monitoring system also includes a plurality of fiber optic sensors for converting at least one of vibrational and acoustical energy to optical intensity information, each of the fiber optic sensors having: (1) at least one length of optical fiber configured to sense at least one of vibrational and acoustical energy; (2) a reflector at an end of the at least one length of optical fiber; and (3) a field node for receiving optical signals from the host node, the field node transmitting optical signals along the at least one length of optical fiber, receiving optical signals back from the at least one length of optical fiber, and transmitting optical signals to the optical receiver of the host node.
    Type: Grant
    Filed: February 17, 2011
    Date of Patent: March 17, 2015
    Assignee: US Seismic Systems, Inc.
    Inventors: Eric Lee Goldner, Gerald Robert Baker, James Kengo Andersen, Agop Hygasov Cherbettchian, Jeffrey Carl Buchholz
  • Patent number: 8970845
    Abstract: A method and system for rendering the shape of a multi-core optical fiber or multi-fiber bundle in three-dimensional space in real time based on measured fiber strain data. Three optical fiber cores arc arranged in parallel at 120° intervals about a central axis. A series of longitudinally co-located strain sensor triplets, typically fiber Bragg gratings, are positioned along the length of each fiber at known intervals. A tunable laser interrogates the sensors to detect strain on the fiber cores. Software determines the strain magnitude (?L/L) for each fiber at a given triplet, but then applies beam theory to calculate curvature, beading angle and torsion of the fiber bundle, and from there it determines the shape of the fiber in s Cartesian coordinate system by solving a series of ordinary differential equations expanded from the Frenet-Serrat equations.
    Type: Grant
    Filed: December 16, 2013
    Date of Patent: March 3, 2015
    Assignee: The United States of America as Represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Hon Man Chan, Allen R. Parker, Jr.
  • Patent number: 8940238
    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: December 3, 2013
    Date of Patent: January 27, 2015
    Assignee: Access Medical Systems, Ltd.
    Inventors: Hong Tan, Yushan Tan, Erhua Cao, Ming Xia, Robert F. Zuk
  • Patent number: 8873064
    Abstract: A fiber-optic sensor can have a Michelson sensor portion and a Mach-Zehnder sensor portion. A first splitter-coupler can be configured to split incoming light between a first fiber portion and a second fiber portion. A first polarization-phase conjugation device can be configured to conjugate a polarization phase of incident light corresponding to the first fiber portion, and a second polarization-phase conjugation device can be configured to conjugate a polarization phase of incident light corresponding to the second fiber portion. Each of the first and second polarization-phase conjugation devices can be configured to reflect light toward a detector and through the respective first and second fiber portions. A coupler can be configured to join light in the first fiber portion with light in the second fiber portion, and a third fiber portion can be configured to receive light from the coupler and to illuminate a second detector.
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: October 28, 2014
    Assignee: Fibersonics Inc.
    Inventor: Edward Tapanes
  • Publication number: 20140300900
    Abstract: An input of an optical interferometer is a periodical optical pulse. A phase of a first half and a latter half of a reference pulse is a 90 degree (independently orthogonal) phase difference. Two interferometric outputs i1 and i2, where the phase difference is 90 degrees from each other, are obtained by interference of the reference pulse and the signal pulse. ? is calculated by referring the amplitude of reference pulse and the signal pulse to remove the light intensity fluctuations. Two values of cos ?1 and cos ?2 are calculated and positions are determined on the cosine curve by obtaining ?1 and ?2 values. ??1 and ??2, which are the phase increment or decrement of both ?1 and ?2 in a T period, are summed and becomes the sensor output signal that removes the measurement range limitation of ±90 degrees (a half wavelength of light) of the light phase.
    Type: Application
    Filed: November 19, 2012
    Publication date: October 9, 2014
    Applicant: Hakusan Corporation
    Inventor: Kazumasa Tsukada
  • Patent number: 8823946
    Abstract: A fiber optic gyroscope including a non-coherent light source for producing a first beam of light, an optical circulator in the path of said first beam for providing polarized second and third beams, respectively, with polarization orthogonal to each other, and a time division multiplexer in the path of the second and third beams. A first planar optical fiber loop is coupled to the time division multiplexer and has a first end and a second end coupled to the second and third beams respectively during a first time period. A second planar optical fiber loop is coupled to the time division multiplexer and has a first end and a second end coupled to the second and third beams respectively during a second time period subsequent to the first time period.
    Type: Grant
    Filed: June 13, 2011
    Date of Patent: September 2, 2014
    Assignee: Emcore Corporation
    Inventors: Ronald T. Logan, Jr., Ka Kha Wong
  • Patent number: 8825434
    Abstract: A temperature measuring method includes: transmitting a light to a measurement point of an object to be measured, the object being a substrate on which a thin film is formed; measuring a first interference wave caused by a reflected light from a surface of the substrate, and a second interference wave caused by reflected lights from an interface between the substrate and the thin film and from a rear surface of the thin film; calculating an optical path length from the first interference wave to the second interference wave; calculating a film thickness of the thin film; calculating an optical path difference between an optical path length of the substrate and the calculated optical path length; compensating for the optical path length from the first interference wave to the second interference wave; and calculating a temperature of the object at the measurement point.
    Type: Grant
    Filed: September 29, 2011
    Date of Patent: September 2, 2014
    Assignee: Tokyo Electron Limited
    Inventors: Chishio Koshimizu, Jun Yamawaku, Tatsuo Matsudo
  • 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