Using Changes In Transmission, Scattering Or Fluorescence In Optical Fibers (epo) Patents (Class 374/E11.015)
  • Patent number: 10564355
    Abstract: A disclosed optical waveguide element includes a cladding portion formed on a substrate; an optical waveguide which is formed inside the cladding portion and has a refractive index higher than that of the cladding portion; an optical filter which is inserted into a slit formed in the cladding portion to divide the optical waveguide into a first optical waveguide and a second optical waveguide; and a first thin film element which is inserted into the slit along with the optical filter and is provided with a first thin film lens, wherein the first thin film lens provided in the first thin film element converges light that has propagated through the first optical waveguide and outputs into the slit into the second optical waveguide.
    Type: Grant
    Filed: November 8, 2018
    Date of Patent: February 18, 2020
    Assignee: FURUKAWA ELECTRIC CO., LTD.
    Inventor: Junichi Hasegawa
  • Patent number: 10422706
    Abstract: The present invention is a temperature sensor for cryogenic systems using a fiber optic interrogation system that is capable of a large number of temperature readings across the cryogenic environment at high resolutions. The invention also includes a method of using such a system to measure temperatures in a cryogenic environment and a method of making such a system.
    Type: Grant
    Filed: June 28, 2018
    Date of Patent: September 24, 2019
    Assignee: United States of America as Represented by the Adminstrator of the National Aeronautics and Space Adminstration
    Inventors: Allen R. Parker, Jr., Anthony Piazza, Hon Man Chan, Ryan M Warner
  • Patent number: 9739142
    Abstract: An apparatus for monitoring vibration of a downhole component includes an optical fiber sensor including at least one optical fiber operably connected to an interrogation unit. The at least one optical fiber has a resonant segment that is fixedly attached to the component via attachment points on the component, the resonant segment between the attachment points being separate from the component and having a resonant frequency based at least on the length of the resonant segment.
    Type: Grant
    Filed: August 14, 2014
    Date of Patent: August 22, 2017
    Assignee: BAKER HUGHES INCORPORATED
    Inventors: Daniel Boyd Cooper, Erik N. Lee
  • Patent number: 9726546
    Abstract: According to an embodiment there is provided a distributed optical sensing apparatus for determining of a primary quantity along a waveguide, the distributed optical sensing apparatus comprising: an electromagnetic radiation source adapted for coupling electromagnetic radiation into the waveguide to thereby generate in the waveguide (e.g. by interaction with the waveguide) a first response radiation and a different second response radiation; a detector device adapted for providing a first measurement signal indicative of the first response radiation and a second measurement signal indicative of the second response radiation; an evaluation unit adapted for deriving a secondary quantity (e.g. a loss) based on the first measurement signal and the second measurement signal; the evaluation unit being further adapted for deriving the primary quantity based on the secondary quantity and at least one of the first measurement signal and the second measurement signal.
    Type: Grant
    Filed: February 13, 2015
    Date of Patent: August 8, 2017
    Assignee: AP Sensing GmbH
    Inventors: Gregor Cedilnik, Gerd Koffmane
  • Patent number: 9488532
    Abstract: A temperature distribution measurement system includes an optical fiber, a laser light source optically connected to the optical fiber, a photodetector configured to detect light backscattered in the optical fiber, and a temperature distribution measurement unit configured to perform correction calculation using a transfer function on a measured temperature distribution obtained from an output from the photodetector. The temperature distribution measurement unit acquires an actual temperature distribution in a location where the optical fiber is laid and determines appropriateness of the transfer function by computing a difference between the measured temperature distribution after the correction and the actual temperature distribution.
    Type: Grant
    Filed: February 5, 2014
    Date of Patent: November 8, 2016
    Assignee: FUJITSU LIMITED
    Inventors: Takeo Kasajima, Kazushi Uno, Minoru Ishinabe, Kyoko Tadaki, Fumio Takei
  • Patent number: 8734011
    Abstract: The present invention discloses distributed optical fiber temperature sensor based on optical fiber delay technology, including a tunable optical transmitter module, an optical receiver module, a signal processing and controlling module and multiple distributed sensing modules connected in series via transmission fibers. The multiple wavelengths optical signals transmitted from the tunable optical transmitter module respectively are transmitted into the first sensing module, and then transmitted out from the last sensing module. The output multiple wavelengths optical signals arrive at the optical receiver module. The optical receiver module converts optical signals of all wavelengths into electrical signals and transmits them into the signal processing and controlling module.
    Type: Grant
    Filed: May 6, 2012
    Date of Patent: May 27, 2014
    Assignee: University of Electronic Science and Technology of China
    Inventors: Qi Qiu, Jun Su, Shuangjin Shi, Yun Liao, Caidong Xiong
  • Publication number: 20130323023
    Abstract: A dynamic fiber temperature sensing package is provided herein. The sensing package includes a support structure, a holder coupled to the support structure, a sheath coupled to the support structure via the holder, and a fiber optic temperature sensor positioned within the sheath. The holder includes a material having a first thermal conductivity and the sheath includes a material having a second thermal conductivity, wherein the second thermal conductivity is greater than the first thermal conductivity.
    Type: Application
    Filed: June 5, 2012
    Publication date: December 5, 2013
    Inventors: Kevin McCarthy, Hua Xia, Juntao Wu, Axel Busboom, Thomas Finucane
  • Publication number: 20130215926
    Abstract: Automated systems and methods for testing the efficacy and reliability of distributed temperature sensing (DTS) system. The DTS system has a fibre optic sensing cable laid out on a structure to be monitored, and a DTS unit for sensing temperature along a sensing line at locations thereof. The DTS unit is optically coupled to the sensing cable. The sensing cable is optically coupled to a test cable to form the sensing line. Also provided, is a cooling device for cooling the test cable. A controller periodically actuates the cooling device to thereby test the efficacy and reliability of the DTS system. A relay configured for communication with the DTS unit and the controller is operable to trigger an alarm condition in response to a signal received from the DTS unit indicative that a temperature drop in the sensing line at a location thereof has been detected.
    Type: Application
    Filed: February 17, 2012
    Publication date: August 22, 2013
    Applicant: ROCTEST LTD.
    Inventors: Riccardo Belli, Daniele Inaudi
  • Publication number: 20130208762
    Abstract: An apparatus and method for suppressing stimulated Raman scattering (SRS) in fiber optic distributed temperature sensing systems by use of a combination of a pump and seed lasers with chosen frequency differences.
    Type: Application
    Filed: February 14, 2012
    Publication date: August 15, 2013
    Inventors: Ian Bradford Mitchell, Mikko Jaaskelamen
  • Publication number: 20130148691
    Abstract: The present invention discloses distributed optical fiber temperature sensor based on optical fiber delay technology, including a tunable optical transmitter module, an optical receiver module, a signal processing and controlling module and multiple distributed sensing modules connected in series via transmission fibers. The multiple wavelengths optical signals transmitted from the tunable optical transmitter module respectively are transmitted into the first sensing module, and then transmitted out from the last sensing module. The output multiple wavelengths optical signals arrive at the optical receiver module. The optical receiver module converts optical signals of all wavelengths into electrical signals and transmits them into the signal processing and controlling module.
    Type: Application
    Filed: May 6, 2012
    Publication date: June 13, 2013
    Inventors: Qi Qiu, Jun Su, Shuangjin Shi, Yun Liao, Caidong Xiong
  • Publication number: 20130100984
    Abstract: The present apparatus includes: an intensity ratio calculation unit configured to calculate a first and a second intensity ratios which are ratios of Stokes light intensity to anti-Stokes light intensity obtained when a light pulse is output to a first end and a second end of an optical fiber, respectively; a temperature calculation unit configured to calculate a temperature distribution along the optical fiber based on a reference temperature, the first and the second intensity ratios, and a total length loss ratio, which is a loss ratio of Stokes light to anti-Stokes light with regard to a total length of the optical fiber; and a total length loss ratio calculation unit configured to calculate the total length loss ratio based on the first and the second intensity ratios with regard to a location in a predetermined section close to both ends of the optical fiber whose temperature is kept constant.
    Type: Application
    Filed: October 23, 2012
    Publication date: April 25, 2013
    Applicant: YOKOGAWA ELECTRIC CORPORATION
    Inventor: YOKOGAWA ELECTRIC CORPORATION
  • Publication number: 20130034122
    Abstract: A temperature sensor includes a photon source, a fluorescent element and a photodetector. The fluorescent element includes a temperature-insensitive first fluorophore and a temperature-sensitive second fluorophore. The photodetector includes a first photosensor exhibiting a first spectral responsivity and a second photosensor exhibiting a second spectral responsivity. The first fluorophore may be selected to optimize the first spectral responsivity and the second fluorophore may be selected to optimize the second spectral responsivity. To measure a temperature of a surface, the fluorescent element may be placed adjacent to the surface and irradiated with a photon beam. First photons emitted from the first fluorophore and second photons emitted from the second fluorophore are collected.
    Type: Application
    Filed: October 5, 2012
    Publication date: February 7, 2013
    Applicant: Research Triangle Institute, International
    Inventor: Research Triangle Institute, International
  • Publication number: 20130034324
    Abstract: An optical fiber sensing apparatus includes: a substrate configured to deform in response to an environmental parameter; an optical fiber sensor including a core having at least one measurement location disposed therein and a protective coating surrounding the optical fiber sensor, the protective coating made from a polyimide material; and an adhesive configured to adhere the optical fiber sensor to the substrate, the adhesive made from the polyimide material.
    Type: Application
    Filed: August 3, 2011
    Publication date: February 7, 2013
    Applicant: BAKER HUGHES INCORPORATED
    Inventors: Malcolm S. Laing, Daniel S. Homa, Robert M. Harman, Christopher H. Lambert
  • Publication number: 20130028289
    Abstract: A dispersion and loss spectrum auto-correction distributed optical fiber Raman temperature sensor has a dual fiber pulsed laser module with dual Raman wavelength shifts. The laser module is composed of a power supply (11), an electronic switch (12), a primary laser (13) and a secondary laser (14), a first combiner (15), a bidirectional coupler (16), a multimode fiber (17), an integrated optical fiber wavelength division multiplexer (18), a second combiner (19), a direct detection system (20), a signal collection and processing system (21) and a display (22). The sensor uses two light sources that have two Raman wavelength shifts, wherein the central wavelength of backward anti-Stokes Raman scattering peak of the primary light source coincides with that of the backward Stokes scattering peak centre wavelength of the secondary light source, and the time domain reflection signal of the one-way optical fiber Rayleigh scattering is deducted.
    Type: Application
    Filed: August 20, 2010
    Publication date: January 31, 2013
    Inventors: Zaixuan Zhang, Chenxia Li, Jianfeng Wang, Xiangdong Yu, Wensheng Zhang, Wenping Zhang, Xiaohui Niu
  • Publication number: 20130008180
    Abstract: A component sensing system for monitoring the condition of ceramic tiles in a combustion chamber of a gas turbine engine. The sensing system includes an optical fiber that is mounted to the component being monitored, for example, the ceramic tiles in the gas turbine combustion chamber. The optical fiber can be formed in any suitable orientation or configuration, such as a meandering or serpentine orientation. The fiber is optically coupled to a Brillouin signal analyzer that provides an optical pulse to the sensing section of the fiber and detects Brillouin backscattering from the fiber as the pulse travels along the fiber. The frequency of the Brillouin backscattering signal is monitored relative to the distance along the sensing section of the fiber. A rise in temperature at a location of the fiber shows up in the analyzer as an increase in frequency of the backscattered signal.
    Type: Application
    Filed: July 7, 2011
    Publication date: January 10, 2013
    Inventors: Evangelos V. Diatzikis, Hans-Gerd Brummel, Michael Twerdochlib
  • Publication number: 20120325001
    Abstract: Optical sensors and sensing methods are provided. A particular method includes applying light to a first end of an optical fiber. Light reflected by at least one of a first photonic crystal sensor coupled to a second end of the optical fiber and a second photonic crystal sensor coupled to the second end of the optical fiber is detected. The first photonic crystal sensor exhibits a first reflection spectrum that changes responsive a first sensed parameter and the second photonic crystal sensor exhibits a second reflection spectrum that changes responsive a second sensed parameter. A parameter value of at least one of the first sensed parameter and the second sensed parameter is determined based on the detected light.
    Type: Application
    Filed: June 27, 2011
    Publication date: December 27, 2012
    Applicant: The Boeing Company
    Inventors: Michael A. Carralero, Ty A. Larsen
  • Publication number: 20120307861
    Abstract: An optical fiber is provided with a first measurement portion and a second measurement portion provided with covering layers different at least in any one of heat capacity and heat conductivity. Then, the first measurement portion and the second measurement portion are located in the same measurement position and light is inputted from a temperature measurement device into the optical fiber. Thereafter, the temperature measurement device receives backscattered light generated inside the optical fiber to measure temperature distribution in a longitudinal direction of the optical fiber. An analyzer analyzes a variation over time of the temperature distribution outputted from the temperature measurement device to calculate a temperature and a wind velocity in a measurement position where the first measurement portion and the second measurement portion are located.
    Type: Application
    Filed: August 1, 2012
    Publication date: December 6, 2012
    Applicant: FUJITSU LIMITED
    Inventors: Fumio Takei, Kazushi Uno, Takeo Kasajima
  • Publication number: 20120281201
    Abstract: A Brillouin analysis sensor system comprising: a Brillouin analysis sensor; a polarization beam splitter/combiner, operably connected to the Brillouin analysis sensor between the sensor and the sensing fibre, for receiving polarized lightwaves from the sensor, combining the lightwaves and launching combined lightwaves waves in the sensing fibre a first direction, and a phase conjugate mirror at a free end of the sensing fibre for receiving combined lightwaves from the polarization beam splitter/combiner, rotating the polarization of the combined lightwaves and launching the rotated combined lightwaves in the sensing fibre in an opposing direction to the first direction.
    Type: Application
    Filed: August 27, 2010
    Publication date: November 8, 2012
    Inventor: Anthony Brown
  • Patent number: 8287184
    Abstract: The present invention relates to a measuring method and a controlling method of measuring the physical quantity such as a fluid temperature distribution and the like by using an optical fiber sensing technique of BOCDA system. In the measuring method, an optical fiber that functions as a BOCDA-type optical fiber sensor is disposed along a flow direction of a fluid that flows though a pipe line and in the pipe line. Since the optical fiber directly contacts with the fluid that flows though the pipe line, it is possible to rapidly measure the fluid temperature distribution. Also, based on this measurement result, the controlling method adjusts each temperature of one or more heating/cooling means provided along the longitudinal direction of a pipe line, thereby controlling at high accuracy the fluid temperature distribution in the pipe line.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: October 16, 2012
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Eisuke Sasaoka
  • Publication number: 20120243572
    Abstract: A temperature measuring apparatus and a temperature measuring method that may simultaneously measure temperatures of objects in processing chambers. The temperature measuring apparatus includes a first light separating unit which divides light from the light source into measurement lights; second light separating units which divide the measurement lights from the first light separating unit into measurement lights and reference lights; third light separating units which further divide the measurement lights into first to n-th measurement lights; a reference light reflecting unit which reflects the reference lights; an light path length changing unit which changes light path lengths of the reference lights reflected by the reference light reflecting unit; and photodetectors which measure interference between the first to n-th measurement lights reflected by the objects to be measured and the reference lights reflected by the reference light reflecting unit.
    Type: Application
    Filed: March 23, 2012
    Publication date: September 27, 2012
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Tatsuo MATSUDO, Chishio KOSHIMIZU
  • Publication number: 20120243573
    Abstract: A plasma processing apparatus and a temperature measuring method that may measure a temperature of an object in a processing chamber by a low-coherence interferometer without forming a hole in a holding stage or an upper electrode of the plasma processing apparatus, thereby performing a plasma process of a substrate with high precision and uniformity. The plasma processing apparatus is implemented by disposing a light source collimator outside of a light source window, disposing a light-receiving collimator outside of a light-receiving window, allowing a measurement light emitted from the light source collimator to pass through the light source window to be obliquely emitted to a surface of the object to be measured, and allowing the reflected measurement light to pass through the light-receiving window to be incident on the light-receiving collimator. The temperature of the object in the processing chamber may be measured by the low-coherence interferometer.
    Type: Application
    Filed: March 23, 2012
    Publication date: September 27, 2012
    Applicant: TOKYO ELECTRON LIMITED
    Inventor: Tatsuo MATSUDO
  • Publication number: 20120183015
    Abstract: Apparatus for spatially resolved temperature measurement, comprising at least one optical fibre (4) for spatially resolved temperature measurement, at least one laser light source (1), the light (11) from which can be coupled into the optical fibre (4), wherein those components (12, 12a, 12b) of the light (11) produced by the laser light source (1) which are scattered back in the optical fibre (4) can be coupled out of the optical fibre (4) and detected, modulator means (2) permitting the modulation of the light (11) that is to be coupled into the optical fibre (4), and also demodulator means (5, 6) which permit a demodulation of those components (12, 12a, 12b) of the light (11) which are coupled out of the optical fibre (4), wherein the demodulator means (5, 6) are designed as optical demodulator means (5, 6) and/or wherein the modulator means (2) are designed as optical modulator means (2).
    Type: Application
    Filed: September 27, 2010
    Publication date: July 19, 2012
    Applicant: LIOS TECHNOLOGY GMBH
    Inventor: Wieland Hill
  • Publication number: 20120170613
    Abstract: A fiber optic splice housing and integral dry mate connector system. In a described embodiment, a fiber optic connection system includes optical fiber sections in respective conduit sections. Each of the conduit sections is received in the housing assembly. An optical connection between the optical fiber sections is positioned within the housing assembly.
    Type: Application
    Filed: March 13, 2012
    Publication date: July 5, 2012
    Applicant: WELLDYNAMICS, B.V.
    Inventors: Paul D. RINGGENBERG, NEAL G. SKINNER, John L. MAIDA, JR., David O. JOHNSON
  • Publication number: 20120170615
    Abstract: A temperature sensor that has an elongated sensing element having a length of at least 10 m, measured at a temperature of 20° C. The elongated sensing element includes an elongated jacket and an optical fiber mounted in the jacket and having an EFL of at least 0.35%, wherein the elongated sensing element has an average temperature error of less than 2° C.
    Type: Application
    Filed: March 14, 2012
    Publication date: July 5, 2012
    Applicant: LXDATA INC
    Inventors: Bai ZHOU, Sébastien MIVILLE, André R. VINCELETTE
  • Publication number: 20120170614
    Abstract: A fiber optic splice housing and integral dry mate connector system. In a described embodiment, a fiber optic connection system includes optical fiber sections in respective conduit sections. Each of the conduit sections is received in the housing assembly. An optical connection between the optical fiber sections is positioned within the housing assembly.
    Type: Application
    Filed: March 13, 2012
    Publication date: July 5, 2012
    Applicant: WELLDYNAMICS, B.V.
    Inventors: Paul D. RINGGENBERG, NEAL G. SKINNER, John L. MAIDA, JR., David O. JOHNSON
  • Publication number: 20120162635
    Abstract: A measuring device including at least one optical fiber which contains a series of Bragg gratings distributed between first and second ends of the fiber. A light source is arranged to emit a luminous flux at multiple wavelengths incident on the first end of the fiber, and an instrument connected to the second end of the fiber measures the power of the light transmitted at each emitted wavelength, enabling implementation of the method. In the method the power of the light transmitted by the optical fiber in a spectrum including wavelengths is measured.
    Type: Application
    Filed: August 19, 2010
    Publication date: June 28, 2012
    Applicant: KLOE S.A.
    Inventors: Nicolas Brillouet, Paul Coudray
  • Publication number: 20120147924
    Abstract: An apparatus for measuring environmental parameters includes: an optical fiber sensor configured to be disposed along a path in an environment to be measured, the path of the optical fiber sensor defining a longitudinal axis; and at least one section of the optical fiber sensor configured so that an entire length of the at least one section is exposed to an at least substantially homogeneous environmental parameter, at least part of the at least one section extending in a direction having a radial component relative to the longitudinal axis.
    Type: Application
    Filed: December 8, 2010
    Publication date: June 14, 2012
    Applicant: BAKER HUGHES INCORPORATED
    Inventor: Travis S. Hall
  • Publication number: 20120120985
    Abstract: A temperature sensor that has an elongated sensing element having a length of at least 10 m, measured at a temperature of 20° C. The elongated sensing element includes an elongated jacket and an optical fiber mounted in the jacket and having an EFL of at least 0.35%, wherein the elongated sensing element has an average temperature error of less than 2° C.
    Type: Application
    Filed: January 3, 2012
    Publication date: May 17, 2012
    Applicant: LXDATA INC
    Inventors: Bai ZHOU, Sébastien MIVILLE, André R. VINCELETTE
  • Publication number: 20120082182
    Abstract: The invention relates to a method for integrating an optical waveguide (3) of a temperature sensor and/or strain sensor into a temperature and/or strain measuring component (1) made of a base material (2), onto which a coating (5) is applied. The optical waveguide (3) is arranged on a predetermined measurement plane, whereupon a coating (5) is applied. The aim of the invention is to allow an optical waveguide (3) to be accurately integrated into and tightly joined to the body of a temperature and/or strain measuring component (1).
    Type: Application
    Filed: June 8, 2010
    Publication date: April 5, 2012
    Applicant: SMS SIEMAG AKTIENGESELLSCHAFT
    Inventor: Gereon Fehlemann
  • Publication number: 20120044971
    Abstract: The polarization-maintaining fiber of the invention includes a core (1) made of germanium doped silica glass; a stress-applying part (3) made of boron doped silica glass; a cladding (2) made of pure silica glass; and a polyimide coating layer (4) with a thickness of 10 ?m or less that surrounds the outer periphery of the cladding (2).
    Type: Application
    Filed: May 20, 2011
    Publication date: February 23, 2012
    Applicant: FUJIKURA LTD.
    Inventors: Koji OMICHI, Yoshihiro Terada, Yutaka Endoh, Kazuyuki Hayashi, Katsuaki Izoe, Kazuhiko Aikawa, Manabu Kudoh
  • Publication number: 20120039358
    Abstract: For a temperature measurement in areas having electromagnetic fields, shielding devices must be provided. According to the proposed technique, at least one temperature sensor is designed as a fiber-optic sensor having Bragg gratings (FBG), wherein the sensor is arranged in a non-metallic housing that precludes or minimizes expansion effects for the individual FBG sensors. For example, the proposed technique can be used advantageously to measure the temperature distribution in oil sand deposits, for which purpose a suitable measuring arrangement is required.
    Type: Application
    Filed: January 28, 2010
    Publication date: February 16, 2012
    Inventors: Thomas Bosselmann, Michael Willsch
  • Publication number: 20120039359
    Abstract: A sensing cable has a sensing fiber assembly, which includes a pair of sensing fibers joined by a turnaround section with a modal filter, at a terminating end of the sensing fibers. The sensing cable also includes an inner sleeve that surrounds the sensing fiber assembly and an armored casing that caps the terminating end of the inner sleeve. The sensing cable has a low profile and its components are each made of high temperature and hydrogen tolerant materials and are capable of prolonged operation at high temperatures, such as up to 300° C., in hydrogen environments over long lengths of fiber. A distributed thermal sensing (DTS) interrogator is connected to the sensing cable and performs DTS measuring according to protocols and algorithms that leverage the modal filter of the turnaround section to calculate temperature readings along the sensing fiber assembly.
    Type: Application
    Filed: August 12, 2011
    Publication date: February 16, 2012
    Applicant: QOREX LLC
    Inventors: TREVOR WAYNE MacDOUGALL, PAUL ERIC SANDERS
  • Publication number: 20120039357
    Abstract: A fiber-optic temperature sensor assembly comprises a cap with an inner cavity. A sensor substance is received loosely in the inner cavity of the cap, the sensor substance having light-emitting properties adapted to change with specific temperature variations. An optical fiber has a first end received in the inner cavity of the cap and fusion spliced thereto, and a second end of the optical fiber being adapted to be connected to a processing unit for transmitting light signals from the sensor substance to the processing unit when the fiber-optic temperature sensor assembly is subjected to specific temperatures. A method for manufacturing the fiber-optic temperature sensor assembly is defined.
    Type: Application
    Filed: August 16, 2010
    Publication date: February 16, 2012
    Inventors: Marc LEVESQUE, Patrick Paradis
  • Publication number: 20120039360
    Abstract: A method for calculating a temperature along a length of a sensing fiber of a distributed thermal sensing (DTS) system. The sensing fiber, which has two ends, is heat resistant for operation up to 300° C. The DTS system includes a two-channel DTS interrogator that is attached to each of the two ends of the sensing fiber. The DTS interrogator interrogates the sensing fiber from both ends, calculates a temperature difference between co-located positions along the length of the sensing fiber for each end, and determines an error associated with the temperature difference. Based on the determined error, a corrected temperature value along the length of the sensing fiber is calculated and outputted.
    Type: Application
    Filed: August 12, 2011
    Publication date: February 16, 2012
    Applicant: QOREX LLC
    Inventors: Trevor Wayne MacDougall, Paul Eric Sanders
  • Publication number: 20120039361
    Abstract: A multi-mode optical waveguide fiber including a central core region having an outer radius surrounded by an inner cladding region having an outer radius, the inner cladding region having a lower index of refraction than the central core region, wherein both the central core and inner cladding regions are doped with fluorine, wherein the refractive index profile of the central core region is of the gradient index type and the central core region in the range of r?[0-ra] comprises germanium at a maximum concentration within the range of 0.5 percent by weight to 4.0 percent by weight taken at a given radius, wherein said fiber has an Overfilled Modal Bandwidth >500 MHz·km at a wavelength of 850 nm and 1300 nm, according to IEC 60793-2-10.
    Type: Application
    Filed: August 12, 2011
    Publication date: February 16, 2012
    Applicant: DRAKA COMTEQ B.V.
    Inventors: Frans GOOIJER, Gertjan KRABSHUIS, Elise REGNIER, Adrian AMEZCUA-CORREA, Pieter MATTHIJSSE, Denis MOLIN
  • Publication number: 20120033709
    Abstract: A temperature measurement system includes: a laser light source; an optical fiber; and a temperature measurement unit configured to acquire a measured temperature distribution of a temperature of a temperature measurement area along an installation path of the optical fiber by detecting backscattered light of the incident laser light in the optical fiber, wherein the temperature measurement unit sequentially makes a correction for the measured temperature distribution a plurality of times so as to make a square error between a convolution of a transfer function of the optical fiber along the installation path and the corrected temperature distribution and the measured temperature distribution smaller in each of the corrections, and the temperature measurement unit also replaces a corrected temperature at a specific point of the installation path with an estimated temperature at the specific point in each of the corrections.
    Type: Application
    Filed: September 12, 2011
    Publication date: February 9, 2012
    Applicant: FUJITSU LIMITED
    Inventors: Takeo KASAJIMA, Kazushi UNO, Fumio TAKEI
  • Publication number: 20120033710
    Abstract: The present invention relates to an optical temperature sensor, comprising: a housing; a light-transmitting unit, installed in the housing, for emitting light transmitted through an optical fiber into an inner space of the housing; and a bimetal device, movably installed in the housing, for varying the amount of transmitted light, wherein the optical temperature sensor is capable of measuring a temperature by using the amount of light, from the light transmitted via the optical fiber, which is shielded through bending due to a change in the temperature of the bimetal device, or using the amount of light, from the transmitted light, which is reflected and received. The optical temperature sensor has a simple structure and is not particularly restricted in terms of installation space.
    Type: Application
    Filed: June 14, 2010
    Publication date: February 9, 2012
    Applicant: OPTOPOWER CO., LTD.
    Inventor: Young Soo Kim
  • Patent number: 8092081
    Abstract: A method and apparatus is provided for determining when a battery, or one or more batteries within a battery pack, undergoes an undesired thermal event such as thermal runaway. The system uses an optical fiber mounted in close proximity to, or in contact with, an external surface of the battery or batteries to be monitored. A source of light is optically coupled to the input facet of the optical fiber and a detector optically coupled to the output facet of the optical fiber. Battery health is determined by monitoring the light transmitted through the optical fiber.
    Type: Grant
    Filed: May 28, 2009
    Date of Patent: January 10, 2012
    Assignee: Tesla Motors, Inc.
    Inventors: Weston Arthur Hermann, Paul Bryan Kreiner, Scott Ira Kohn, Dorian West, Jonathan Louis Hall
  • Publication number: 20110310925
    Abstract: There is provided an optical fiber temperature distribution measuring device which measures a temperature distribution along an optical fiber (3) using backward Raman scattering light generated in the optical fiber. The device includes: a reference temperature thermometer (11) disposed in the vicinity of the optical fiber so as to measure a reference temperature (T1, T2) of the optical fiber; an arithmetic controller (7) that calculates a temperature (T) of the optical fiber based on the backward Raman scattering light; and a temperature corrector (12) that corrects the calculated temperature (T) based on a correction formula containing the reference temperature as a parameter.
    Type: Application
    Filed: June 21, 2011
    Publication date: December 22, 2011
    Applicant: YOKOGAWA ELECTRIC CORPORATION
    Inventor: Hisao AGAWA
  • Publication number: 20110280277
    Abstract: Systems and methods for extending the range of a fiber optic DTS system are provided. In one respect, a method may provide steps for transmitting, in a first time period, an optical signal at a first energy level through an optical fiber, collecting backscatter signals as a result of the first transmission, adjusting the first energy level to a second energy level, transmitting, in an additional time period, the adjusted optical signal through the optical fiber, collecting backscatter signals as a result of the adjusted transmissions, and using a portion of the collected backscatter as a result of the first transmission and a portion of the collected backscatter as a result of the additional transmissions, determining one or more parameter profiles, such as a temperature profile.
    Type: Application
    Filed: January 17, 2009
    Publication date: November 17, 2011
    Inventors: Lee Chung, Kalar Kent, Mahesh Ajgaonkar, Michael Sanders
  • Publication number: 20110280280
    Abstract: This invention teaches the fiber optic sensors temperature sensors for cryogenic temperature range with improved sensitivity and resolution, and method of making said sensors. In more detail, the present invention is related to enhancement of temperature sensitivity of fiber optic temperature sensors at cryogenic temperatures by utilizing nanomaterials with a thermal expansion coefficient that is smaller than the thermal expansion coefficient of the optical fiber but larger in absolute value than the thermal expansion coefficient of the optical fiber at least over a range of temperatures.
    Type: Application
    Filed: May 11, 2010
    Publication date: November 17, 2011
    Inventor: Vladimir Kochergin
  • Publication number: 20110144790
    Abstract: Various embodiments of thermal sensing systems and methods for monitoring thermal conditions in such material processing assemblies are described. The thermal sensing systems include a sensor cable that incorporates or is coupled to one or more thermal sensors. The sensor cable is positioned in the assembly and the thermal sensors provide temperature measurements. In various embodiments, the sensor cable and thermal sensors may be optical or electrical devices.
    Type: Application
    Filed: June 23, 2010
    Publication date: June 16, 2011
    Inventors: Terry Gerritsen, Phillip Shadlyn, Richard MacRosty
  • Publication number: 20110135245
    Abstract: An optical fiber with long period fiber gratings includes an optical fiber axis, a core region extending along the fiber axis, the core region having a core refractive index, a cladding region surrounding the core region, the cladding having a cladding refractive index, and a plurality of microholes perpendicular to the fiber axis with a portion of the core region removed, the plurality of microholes are spaced apart by a grating period.
    Type: Application
    Filed: December 8, 2009
    Publication date: June 9, 2011
    Applicant: THE HONG KONG POLYTECHNIC UNIVERSITY
    Inventors: Dongning Wang, Ying Wang, Minwei Yang
  • Publication number: 20110128990
    Abstract: An optical fiber temperature sensor includes an optical transceiver module, a transmission fiber and a sensing head. When the transmission fiber is a polarization maintaining fiber, the sensing head includes a temperature sensing element and a fiber reflector, the temperature sensing element is a section of polarization maintaining fiber. The transmission fiber is fusion spliced with the temperature sensing element, an angle between a polarization axis of the transmission fiber and that of the temperature sensing element is 45 degree at the fusion splicing point. When the transmission fiber is a single-mode fiber, the sensing head includes a polarizer. An angle between a polarization axis of the polarization maintaining fiber connecting the temperature sensing element with the polarizer and that of the polarization maintaining fiber of the temperature sensing element is 45 degree at the fusion splicing point. The present invention is of simple principle and structure, and facilitates manufacturing.
    Type: Application
    Filed: September 7, 2010
    Publication date: June 2, 2011
    Inventors: Shudong Wu, Wenbo Wang
  • Publication number: 20110102803
    Abstract: A single fiber Mach-Zehnder interferometer comprises an optical fiber having a core region and a cladding surrounding the core region, and a micro-cavity having part of the cladding and the core region removed, wherein the micro-cavity is adapted to receive a light beam and separate the light beam into a first light beam that propagates through the micro-cavity in an unguided mode, and a second light beam that propagates through the core region in a guided mode.
    Type: Application
    Filed: November 2, 2009
    Publication date: May 5, 2011
    Applicant: THE HONG KONG POLYTECHNIC UNIVERSITY
    Inventors: Dongning Wang, Ying Wang, Minwei Yang
  • Publication number: 20110090936
    Abstract: Systems and methods are disclosed for distributed temperature and strain sensing along a length of an infrastructure. Two optical sources, such as, external cavity lasers with a narrow linewidth, are used for launching a probe signal into a sensing fiber coupled to the infrastructure, and for producing a local oscillation signal, respectively. The optical sources are coherently locked with a predefined frequency offset with respect to each other, the predefined frequency offset being in the order of the Brillouin frequency shift. The optical sources are included in an optical phase lock loop (OPLL) system. A balanced heterodyne receiver for narrow band detection at radio frequency (RF) bandwidth receives an optical signal generated by coherent mixing of a backscattered probe signal with the Brillouin frequency shift and the local oscillation signal, and produces an output indicative of one or both of a measured temperature and a measured strain.
    Type: Application
    Filed: October 21, 2010
    Publication date: April 21, 2011
    Applicant: Redfern Integrated Optics, Inc.
    Inventor: Vladimir Kupershmidt
  • Publication number: 20110058590
    Abstract: Apparatus for a spatially resolved temperature measurement, with at least one optical fiber (6) for the spatially resolved temperature measurement, and at least one laser light source (2) producing light (3, 23) which can be coupled into the optical fiber (6), wherein the portions of the light (3, 23) backscattered in the optical fiber (6) can be coupled out of the optical fiber (6) and evaluated. The apparatus further includes means for reducing polarization-induced effects, wherein the means may be, for example, a polarization modifier (4) capable of at least partially depolarizing the light (3).
    Type: Application
    Filed: November 12, 2010
    Publication date: March 10, 2011
    Applicant: LIOS Technology GmbH
    Inventor: Wieland HILL
  • Publication number: 20110044371
    Abstract: A distributed optical fiber sensor system is provided. In this system, backward-scattered light generated in a test optical fiber is filtered to separate the backward-scattered light into Raman scattered light and Brillouin scattered light. The separated Raman scattered light and Brillouin scattered light are each converted into digital data. A change in temperature with respect to the distance of the test optical fiber is measured from the digital data of the Raman scattered light. A change in temperature and a change in the degree of deformation with respect to the distance of the test optical fiber are measured from the digital data of the Brillouin scattered light. The change in temperature and the change in the degree of deformation with respect to the distance of the test optical fiber are separately output using the measured data.
    Type: Application
    Filed: June 27, 2009
    Publication date: February 24, 2011
    Applicant: UTO INTERNATIONAL CORPORATION
    Inventor: Michael Lee
  • Publication number: 20100220765
    Abstract: An optical fibre temperature sensor comprising: an optical pulse generator; an optical fibre into which said optical pulses are fed; an optical receiver to receive said optical pulses reflected by said optical fibre and to convert them into an electrical signal; a processor which receives said electrical signal and determines the temperature along said optical fibre; said optical receiver comprising a first filter and a second filter to filter said optical pulse reflected by said optical fibre, characterised in that said first and said second filters filter two adjacent portions of anti-Stokes optical signals or of Stokes optical signals
    Type: Application
    Filed: July 25, 2008
    Publication date: September 2, 2010
    Inventors: Mario Martinelli, Riccardo Belli
  • Publication number: 20100135355
    Abstract: A method and apparatus is provided for determining when a battery, or one or more batteries within a battery pack, undergoes an undesired thermal event such as thermal runaway. The system uses an optical fiber mounted in close proximity to, or in contact with, an external surface of the battery or batteries to be monitored. A source of light is optically coupled to the input facet of the optical fiber and a detector optically coupled to the output facet of the optical fiber. Battery health is determined by monitoring the light transmitted through the optical fiber.
    Type: Application
    Filed: May 28, 2009
    Publication date: June 3, 2010
    Applicant: Tesla Motors, Inc.
    Inventors: Weston Arthur Hermann, Paul Bryan Kreiner, Scott Ira Kohn, Dorian West, Jonathan Louis Hall