Resonant Loop Patents (Class 356/461)
  • Patent number: 11920933
    Abstract: Techniques for reducing the bias error present in optical gyroscopes is disclosed. Such techniques include at least one path length adjustment member placed in an optical gyroscope resonator, which are configured to modulate the optical path length of the resonator so that bias errors attributable to the optical path length are shifted outside of the bandwidth of the optical gyroscope. In some embodiments, the at least one path length adjustment member includes a plurality of microheaters coupled to the resonator, in which case optical path length modulation is achieved by heating the resonator via the microheaters. Alternatively, a plurality of piezo-electric regions can be placed in the resonator, which enables optical path length modulation through electric field gradients applied to the piezo-electric regions.
    Type: Grant
    Filed: February 9, 2021
    Date of Patent: March 5, 2024
    Assignee: Honeywell International Inc.
    Inventors: Jianfeng Wu, Matthew Wade Puckett, Karl D. Nelson
  • Patent number: 11624615
    Abstract: The present disclosure relates to integrated photonics-based optical gyroscopes with silicon nitride (SiN) waveguide-based microresonators. SiN microresonators are fabricated either on a fused silica platform or on a silicon substrate with oxide cladding. A narrow linewidth high-Q laser is hybridly integrated on a silicon photonics platform. The laser is tuned with a first SiN microresonator, and the rotational sensing component of the gyroscope comprises another SiN microresonator. The silicon photonics front-end chip has components for a balanced detection scheme to cancel noise in the optical signal coming back from the rotational sensing component.
    Type: Grant
    Filed: October 4, 2021
    Date of Patent: April 11, 2023
    Assignee: Anello Photonics, Inc.
    Inventor: Mario Paniccia
  • Patent number: 11624635
    Abstract: The present invention provides a method for realizing high stability of micro-nano optical fiber sagnac loop output by means of filter mode control, and belongs to the field of photoelectric detection technologies. In the present invention, the optical filter is combined with the micro-nano optical fiber Sagnac interference structure so as to control the Sagnac in-loop working mode by use of the mode selection characteristics of the filter. In this way, the interference mode is suppressed to better concentrate energy on the working mode, thereby improving the spectrum output uniformity and stability of the Sagnac loop. Further, the reflection and transmission modes of the optical filter do not participate in interference spectrum output and thus the performance of the system will not be affected. By designing and changing the parameters of the optical filter, the output characteristics of the interferometer can be dynamically controlled.
    Type: Grant
    Filed: June 21, 2021
    Date of Patent: April 11, 2023
    Assignee: SHANDONG UNIVERSITY OF SCIENCE AND TECHNOLOGY
    Inventors: Lijun Li, Tianzong Xu, Qian Ma, Xiaolei Liu, Jianhong Sun, Zhaochuan Zhang
  • Patent number: 11566900
    Abstract: A sensor for measuring rate of rotation is disclosed which includes a disk resonator, an anchor coupled to the disk resonator and further coupled to a substrate, and an optical waveguide wrapping around at least a portion of the perimeter of the disk resonator, the optical waveguide having an input end and an output end, wherein the disk resonator is configured to expand radially when subject to a rotational input, and wherein said radial expansion is adapted to cause a change in an optical signal passing through the optical waveguide.
    Type: Grant
    Filed: March 5, 2020
    Date of Patent: January 31, 2023
    Assignee: Purdue Research Foundation
    Inventor: Sunil Bhave
  • Patent number: 11506495
    Abstract: Systems and methods for an injection locking RFOG are described herein. In certain embodiments, a system includes an optical resonator. The system also includes a laser source configured to launch a first laser for propagating within the optical resonator in a first direction and a second laser for propagating within the optical resonator in a second direction that is opposite to the first direction, wherein the first laser is emitted at a first launch frequency and the second laser is emitted at a second launch frequency. Moreover, the system includes at least one return path that injects a first optical feedback for the first laser and a second optical feedback for the second laser, from the optical resonator, into the laser source, wherein the first and second optical feedbacks respectively lock the first and second launch frequencies to first and second resonance frequencies of the optical resonator.
    Type: Grant
    Filed: July 27, 2020
    Date of Patent: November 22, 2022
    Assignee: Honeywell International Inc.
    Inventors: Jianfeng Wu, Karl D. Nelson, Matthew Wade Puckett, Glen A. Sanders, Lee K. Strandjord
  • Patent number: 11493342
    Abstract: A chip-scale gyrometric apparatus is disclosed. In embodiments, the chip-scale gyrometric apparatus includes a dielectric substrate and an antenna element attached thereto for receiving an inbound signal having an initial phase. The apparatus includes a splitter for splitting the inbound signal into two equivalent signals, and two coils connected to the splitter. The first coil carries one of the split signals in a clockwise (CW) path relative to a rotational axis, while the second coil carries the other split signal in a counterclockwise (CCW) path relative to the same axis. An integrated circuit (IC) on the substrate and connected to the first and second coils measures a phase shift between the first and second signals (e.g., deviation from the initial phase) based on their respective CW and CCW paths and determines, based on the measured phase shift, a degree of rotation relative to the common rotational axis.
    Type: Grant
    Filed: January 17, 2020
    Date of Patent: November 8, 2022
    Assignee: Rockwell Collins, Inc.
    Inventors: Reginald D. Bean, Nathaniel P. Wyckoff, Jeremiah Wolf
  • Patent number: 11486706
    Abstract: A method for reducing or eliminating bias instability in a SBS laser gyroscope comprises introducing a first pump signal propagating in a CW direction, and a second pump signal propagating in a CCW direction in a resonator; generating a CCW first-order SBS signal and a CW first-order SBS signal in the resonator; increasing a power level of the first pump signal above a threshold level such that the CW first-order SBS signal generates a CCW second-order SBS signal; and increasing a power level of the second pump signal above the threshold level such that the CCW first-order SBS signal generates a CW second-order SBS signal. Above the threshold level, an intensity fluctuation of the first-order SBS signals disappear and their DC power are clamped at substantially the same power level. A Kerr effect bias instability of the SBS laser gyroscope is reduced or eliminated by the clamped first-order SBS signals.
    Type: Grant
    Filed: April 24, 2020
    Date of Patent: November 1, 2022
    Assignee: Honeywell International Inc.
    Inventors: Jianfeng Wu, Matthew Wade Puckett, Karl D. Nelson
  • Patent number: 11422060
    Abstract: According to examples, a Brillouin and Rayleigh distributed sensor may include a first laser source to emit a first laser beam, and a second laser source to emit a second laser beam. A photodiode may acquire a beat frequency between the two laser beams. The beat frequency may be used to maintain a predetermined offset frequency shift between the two laser beams. A modulator may modulate the first laser beam. The modulated first laser beam is to be injected into a device under test (DUT). A coherent receiver may acquire a backscattered signal from the DUT. The backscattered signal results from the modulated first laser beam injected into the DUT. The coherent receiver may use the second laser beam as a local oscillator to determine Brillouin and Rayleigh traces with respect to the DUT based on the predetermined offset frequency shift.
    Type: Grant
    Filed: December 1, 2020
    Date of Patent: August 23, 2022
    Assignee: VIAVI SOLUTIONS INC.
    Inventor: Vincent Lecoeuche
  • Patent number: 11402211
    Abstract: Improvements to optical power regulation in a gyroscopic system are described. The system can include an optical assembly (e.g., optical bench) which couples opposing optical signals to a resonator coil. The system can monitor the power of the optical signals through the resonator coil by including signal extraction optics in the optical assembly which are configured to extract a portion of the optical signals. The portions can be extracted via a single beamsplitter, wherein the beamsplitter reflects the portions at a single common surface, and can also reflect the portions to a respective photodetector in free space free from intervening optical components, such as polarizers or beamsplitters. One or more processors can be coupled to the optical assembly, wherein the processor(s) are configured to adjust the power of the optical signals in response to detecting a power difference between the optical signals.
    Type: Grant
    Filed: October 22, 2020
    Date of Patent: August 2, 2022
    Assignee: Honeywell International Inc.
    Inventors: Neil A. Krueger, Glen A. Sanders, Lee K. Strandjord, Marc Smiciklas
  • Patent number: 11362479
    Abstract: A non-reciprocal optical assembly for injection locking a laser to a resonator is described. The laser emits a light beam, and the resonator receives the light beam and returns a feedback light beam to the laser such that the feedback light beam causes injection locking. The non-reciprocal optical assembly is interposed between and optically coupled to the laser and the resonator. The non-reciprocal optical assembly includes a first port that receives the light beam from the laser, and a second port that outputs the light beam to the resonator and receives the feedback light beam from the resonator. The first port also outputs the feedback light beam to the laser. The light beam passes through the non-reciprocal optical assembly with a first power loss, and the feedback light beam passes through the non-reciprocal optical assembly with a second power loss (the first power loss differs from the second power loss).
    Type: Grant
    Filed: September 30, 2019
    Date of Patent: June 14, 2022
    Assignee: GM CRUISE HOLDINGS LLC
    Inventors: Vladimir Ilchenko, Lutfollah Maleki, Ivan Grudinin
  • Patent number: 11204246
    Abstract: Systems and methods are provided to reduce at least one differential harmonics of a resonance tracking modulation in a resonant fiber optic gyroscope (RFOG). The fundamental frequency of the resonance tracking modulation of each of the clockwise and counter clockwise optical signals is substantially identical; however, the amplitude and phase of the Nth harmonic of a clockwise (CW) resonance tracking modulation and the Nth harmonic of a clockwise (CCW) resonance tracking modulation may differ due to non-linearities in the RFOG. Embodiments of the invention diminish, e.g., reduce to zero such vectoral difference. Differential harmonics may be generated at one or more harmonics.
    Type: Grant
    Filed: June 12, 2020
    Date of Patent: December 21, 2021
    Assignee: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Norman Gerard Tarleton, Chuck Croker
  • Patent number: 11187532
    Abstract: Aspects of the present disclosure are directed to configurations of compact ultra-low loss integrated photonics-based waveguides for optical gyroscope applications, and the methods of fabricating those waveguides for ease of large scale manufacturing. Four main process flows are described: (1) process flow based on a repeated sequence of oxide deposition and anneal; (2) chemical-mechanical polishing (CMP)-based process flow followed by wafer bonding; (3) Damascene process flow followed by oxide deposition and anneal, or wafer bonding; and (4) CMP-based process flows followed by oxide deposition. Any combination of these process flows may be adopted to meet the end goal of fabricating optical gyroscope waveguides in one or more layers on a silicon substrate using standard silicon fabrication technologies.
    Type: Grant
    Filed: March 5, 2021
    Date of Patent: November 30, 2021
    Assignee: ANELLO PHOTONICS, INC.
    Inventors: Mario Paniccia, Avi Feshali
  • Patent number: 11175140
    Abstract: A resonant fiber optic gyroscope (RFOG) comprises two integrated photonics interfaces coupling the optical resonator coil to the multi-frequency laser source that drives the RFOG; wherein the two integrated photonics interfaces comprise a first waveguide layer and a second waveguide layer wherein the first waveguide layer comprises two waveguide branches which come together to form a single waveguide branch; the second waveguide layer comprises two waveguide branches which remain separate from each other; and wherein the waveguide structure is configured to match an integrated photonics mode to a fiber mode supported by an optical fiber.
    Type: Grant
    Filed: September 10, 2019
    Date of Patent: November 16, 2021
    Assignee: Honeywell International Inc.
    Inventors: Matthew Wade Puckett, Neil A. Krueger, Glen A. Sanders
  • Patent number: 11079233
    Abstract: A stimulated Brillouin scattering gyroscope is provided. A pump laser generates continuous wave (CW) energy that travels through at least one bus waveguide to a waveguide resonator. A reflector is positioned within the waveguide resonator. The reflector is configured to pass at least some of the CW energy in a first direction and reflect at least some stimulated Brillouin scattering (SBS) energy in a second direction. A first detector is in operational communication with the at least one bus waveguide to detect CW energy. An output of the first detector used to at least adjust a pump laser frequency of the pump laser. A second detector is also in operational communication with the at least one bus waveguide. The second detector is used to determine phase shifts in detected SBS energy to determine at least rotation.
    Type: Grant
    Filed: September 18, 2019
    Date of Patent: August 3, 2021
    Assignee: Honeywell International Inc.
    Inventors: Jianfeng Wu, Matthew Wade Puckett, Steven Tin
  • Patent number: 11079232
    Abstract: A device includes an optical resonator having four ports including a first port, a second port, a third port, and a fourth port. A first electronic circuit is configured to calculate a first information representative of a power difference between optical signals supplied by two of the four ports. A method of operating a device is also disclosed.
    Type: Grant
    Filed: July 15, 2019
    Date of Patent: August 3, 2021
    Assignee: STMicroelectronics S.R.L.
    Inventors: Antonio Fincato, Enrico Stefano Temporiti Milani, Maurizio Zuffada, Angelica Simbula
  • Patent number: 11002544
    Abstract: Systems and methods for performing resonator fiber optic gyroscope (RFOG) resonance hopping are described herein. For example, an RFOG includes a fiber optic resonator. The RFOG also includes a plurality of laser sources that each launch a respective laser for propagation within the fiber optic resonator. Further, the RFOG includes a threshold detector that determines when the operation of at least one laser source in the plurality of laser sources exceeds a threshold associated with the operational range of an aspect of the at least one laser source. Additionally, the RFOG includes a hop control logic that adjusts the frequency of at least one laser produced by the at least one laser source one or more resonant modes of the fiber optic resonator such that the aspect of the at least one laser moves away from the threshold towards a nominal value within the operational range.
    Type: Grant
    Filed: January 3, 2020
    Date of Patent: May 11, 2021
    Assignee: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Marc Smiciklas, Jianfeng Wu, Glen A. Sanders
  • Patent number: 10741989
    Abstract: A pumped optical ring laser sensor such as a gyroscope includes a pulsed laser source to generate optical pump pulses and a synchronously pumped ring laser. The ring laser is optically pumped by first optical pump pulses from the pulsed laser source that are directed in a clock-wise (CW) direction through the ring laser and by second optical pump pulses from the pulsed laser source that are directed in a counter-clock wise (CCW) direction through the ring laser. The ring laser has an optical resonator that includes a gain medium for producing CW and CCW frequency-shifted pulses from the first and second optical pump pulses. The ring laser further includes a port for receiving the first and second pump pulses and for extracting the CW and CCW frequency-shifted pulses from the ring laser such that the frequency-shifted pulses overlap in time after being extracted to generate a beatnote.
    Type: Grant
    Filed: January 25, 2016
    Date of Patent: August 11, 2020
    Assignee: ARIZONA BOARD OF REGENTS ON BEHALF OF THE UNIVERSITY OF ARIZONA
    Inventor: Khanh Kieu
  • Patent number: 10731987
    Abstract: A stimulated Brillouin scattering (SBS) gyroscope comprises a resonator; a first laser in communication with the resonator and configured to emit a first optical signal propagating in a first direction, the first optical signal producing a first SBS signal counter-propagating in a second direction; a second laser in communication with the resonator and configured to emit a second optical signal propagating in the first direction, the second optical signal producing a second SBS signal counter-propagating in the second direction; a third laser in communication with the resonator and configured to emit a third optical signal propagating in the second direction, the third optical signal producing a third SBS signal counter-propagating in the first direction. At least one photodetector is coupled to the resonator and receives the SBS signals, which are combined in the photodetector to produce electrical signals that include rotational rate information encoded in frequencies of the electrical signals.
    Type: Grant
    Filed: November 2, 2018
    Date of Patent: August 4, 2020
    Assignee: Honeywell International Inc.
    Inventors: Arthur Savchenko, Matthew Wade Puckett
  • Patent number: 10680715
    Abstract: An OMA controller circuit utilizes a first ADC with an input coupled for receiving a residual error signal indicating a difference between a monitoring signal and a target data signal. A second ADC has an input coupled for receiving the target data signal. A first digital filter has an input coupled to an output of the first ADC, and a second digital filter has an input coupled to an output of the second ADC. A digital multiplier has a first input coupled to an output of the first digital filter and a second input coupled to an output of the second digital filter. An integrator has an input coupled to an output of the digital multiplier and an output providing an average error signal with sign and magnitude. The digital multiplier uses a four quadrant multiplier to perform a cross-correlation on the residual error and the target data signal.
    Type: Grant
    Filed: July 22, 2019
    Date of Patent: June 9, 2020
    Assignee: Semtech Corporation
    Inventors: Jonah Edward Nuttgens, Andrew Hana, James Stephen Mason
  • Patent number: 10578438
    Abstract: Various embodiments may provide an optical gyroscope. The optical gyroscope may include a ring resonator, an input source configured to generate or provide a first light beam and a second light beam to the ring resonator, and a switching pathway having an input end and an output end coupled to the ring resonator, and may include a plurality of switches. The optical gyroscope may include a control circuit configured to control the plurality of switches to allow the first light beam to propagate from the input end to the output end along the switching pathway during a first time interval, and allow the second light beam to propagate from the input end to the output end along the switching pathway during a second time interval. The optical gyroscope may additionally include a detector loop configured to receive the first light beam and the second light beam from the ring resonator.
    Type: Grant
    Filed: January 24, 2017
    Date of Patent: March 3, 2020
    Assignee: Agency for Science, Technology and Research
    Inventors: Guoqiang Wu, Jifang Tao, Alex Yuandong Gu, Junfeng Song
  • Patent number: 10503048
    Abstract: An optical resonator system comprises an optical resonator (30) and means (32, 42, 44) for coupling into the resonator counterpropagating waves at total intensities such as to produce a non-linear interaction between the first and second waves whereby to break the symmetry to establish different resonant frequencies between the first and second counterpropagating waves whereby to produce different optical effects in the opposite directions. A common light source, e.g. a laser 32, is employed with an amplifier 40 and a modulator 50, or different light sources can be employed.
    Type: Grant
    Filed: June 23, 2017
    Date of Patent: December 10, 2019
    Assignee: NPL Management Limited
    Inventors: Leonardo Del Bino, Sarah Louise Stebbings, Pascal Patrice Del'Haye, Jonathan Michael Silver
  • Patent number: 10502585
    Abstract: A method comprises supplying an optical input to an interferometric fiber optic gyro (IFOG) at a first frequency and then a different second frequency; detecting a difference in responses of the IFOG to the optical input at the first and second frequencies; and computing a gyro rate as a function of the difference and a correction term.
    Type: Grant
    Filed: October 23, 2014
    Date of Patent: December 10, 2019
    Assignee: The Boeing Company
    Inventors: Shaun M. Detloff, James K. Gingrich
  • Patent number: 10488266
    Abstract: An interferometer including a master laser, a slave laser and optical elements is provided. The optical elements direct and combine a master laser beam and a slave laser beam into a sensing phase measurement loop to provide a sensing beat signal and a reference phase lock loop to provide a reference beat signal. An electronic circuit portion is coupled to receive the sensing and reference beat signals. The electronic circuit portion includes a clock, at least one numerically controlled oscillator, at least one mixer and an interferometer output. The at least one numerically controlled oscillator has a clock input coupled to the clock. The at least one mixer has a first input to receive the sensing beat signal and a second input to receive an output of the at least one numerically controlled oscillator. The interferometer output is coupled to receive an output of the at least one mixer.
    Type: Grant
    Filed: January 23, 2018
    Date of Patent: November 26, 2019
    Assignee: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Glen A. Sanders, Mitchell Novack
  • Patent number: 10436811
    Abstract: A laser-source assembly that is configured to illuminate a vacuum chamber containing atoms in the gaseous state so as to implement a cold-atom inertial sensor, the atoms having at least two fundamental levels that are separated by a fundamental frequency difference comprised between 1 and a few gigahertz, the assembly comprises: a master laser that emits a beam having a master frequency; a first control loop that is configured to stabilize the master frequency of the master laser on a frequency corresponding to half a set frequency of an atomic transition between a fundamental level and an excited level of the atoms; a slave laser that has a slave frequency; and a second control loop that is configured to stabilize the slave frequency of the slave laser with respect to the master frequency, the slave frequency being offset with respect to the master frequency successively, over time, by a first preset offset value, a second preset offset value, and a third preset offset value, the offset values being comprise
    Type: Grant
    Filed: November 7, 2016
    Date of Patent: October 8, 2019
    Assignee: THALES
    Inventors: Matthieu Dupont-Nivet, Sylvain Schwartz, Arnaud Brignon, Jérôme Bourderionnet
  • Patent number: 10429187
    Abstract: A method comprises: receiving a first optical signal and a second optical signal; injecting a portion of the first optical signal into an optical resonator; injecting a portion of the second optical signal into the optical resonator, where the first optical signal and the second optical signal propagate in opposite directions in the optical resonator; emitting a portion of the first optical signal; emitting a portion of the second optical signal; coupling, by free space optics, a portion of the emitted first optical signal to a first power detector; coupling, by free space optics, a portion of the emitted second optical signal to a second power detector; adjusting the power level of the received first optical signal based upon a first detected power level detected by the first power detector; and adjusting the power level of the received second optical signal based upon a second detected power level detected by the second power detector.
    Type: Grant
    Filed: September 4, 2018
    Date of Patent: October 1, 2019
    Assignee: Honeywell International Inc.
    Inventors: Glen A. Sanders, Lee K. Strandjord, Neil A. Krueger, Edward Summers, Clarence Eugene Laskoskie
  • Patent number: 10386187
    Abstract: Ring laser gyroscopes, in which rotation is detected by the Sagnac effect between counterpropagating lasers, are in common use in navigation applications. The invention disclosed here uses lasers operating at different frequencies; the resulting device is referred to as a Nondegenerate Ring Laser Gyroscope (NRLG). The invention disclosed here also incorporates an acceleration-sensing element that modifies the path length of the ring lasers in the gyroscope, the effects of which on the output of the gyroscope can be separated from those of rotation. The resulting composite device is a Nondegnerate Ring Laser Gyroscope/Accelerometer (NRLGA).
    Type: Grant
    Filed: January 18, 2017
    Date of Patent: August 20, 2019
    Assignee: Digital Optics Technologies, Inc.
    Inventors: Selim M. Shahriar, Nicholas J. Condon, Devin J. Hileman, Shih C. Tseng
  • Patent number: 10371524
    Abstract: A passive resonant optical gyroscope comprising a cavity and operating with three frequencies comprises: a first injecting laser to inject a first optical beam into the cavity in a first direction; a second injecting laser to inject a second optical beam into the cavity in an opposite direction; a third injecting laser to inject a third optical beam into the cavity in one of the aforementioned directions, one laser amongst the injecting lasers having a master frequency, the two other injecting lasers, called the first and second slave lasers, respectively having a first slave frequency and a second slave frequency; a master servocontrol device; a first servocontrol stage comprising first and second slave devices; and a second servocontrol stage comprising first and second optical phase-locking devices respectively comprising a first and second slave oscillator to generate a first radiofrequency offset signal and a second radiofrequency offset signal.
    Type: Grant
    Filed: April 5, 2017
    Date of Patent: August 6, 2019
    Assignees: THALES, CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE, ECOLE NORMALE SUPERIEURE DE CACHAN
    Inventors: Sylvain Schwartz, Gilles Feugnet, Arnaud Brignon, Fabien Bretenaker
  • Patent number: 10260881
    Abstract: An interface for a hollow core fiber is provided that facilitates the direct pigtailing of the hollow core fiber to a port on an electro-optic device. The interface includes an angled face that attaches to the electronic device at an angle that minimizes optical power loss as light propagates from the electronic device to the hollow core fiber.
    Type: Grant
    Filed: May 30, 2017
    Date of Patent: April 16, 2019
    Assignee: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Steven Kim, Ricardo A. Rosete, Ragini Saxena
  • Patent number: 10197397
    Abstract: Systems and methods for a small low cost resonator fiber optic gyroscope (RFOG) with reduced optical errors are provided. In one embodiment, a RFOG comprises: a light source; an optical chip configured to couple a clockwise optical signal and a counterclockwise optical signal from the light source into a fiber optic resonator and couple the clockwise optical signal and the counterclockwise optical signal from the fiber optic resonator to at least one photodetector. The fiber optic resonator comprises a fiber optic coil having a first end point and a second end point. The fiber optic coil has a 90-degree splice located substantially half-way between the first end point and the second end point, is wrapped around a first fiber stretcher located between the first end point and the 90-degree splice, and is wrapped around a second fiber stretcher that is located between the second end point and the 90-degree splice.
    Type: Grant
    Filed: October 28, 2014
    Date of Patent: February 5, 2019
    Assignee: Honeywell International Inc.
    Inventors: Glen A. Sanders, Lee K. Strandjord, Tiequn Qiu, Jianfeng Wu
  • Patent number: 10186838
    Abstract: According to one embodiment, a semiconductor light-emitting element includes a ring-shaped light-emitting portion provided on a substrate, a mode-control light waveguide of Si provided on an upper or a lower surface side of the light-emitting portion, and including at least two portions located close to the light-emitting portion, and an output light waveguide of Si provided on the upper or the lower surface side, and including a portion located close to the light-emitting portion. The mode-control light waveguide has a structure for coupling light traveling in one of a clockwise circulating mode and a counterclockwise circulating mode, and feeding back the light in the other of the clockwise circulating mode and the counterclockwise circulating mode.
    Type: Grant
    Filed: February 28, 2017
    Date of Patent: January 22, 2019
    Assignees: KABUSHIKI KAISHA TOSHIBA, Photonics Electronics Technology Research Association
    Inventors: Hirotaka Uemura, Haruhiko Yoshida, Kazuya Ohira, Mizunori Ezaki, Norio Iizuka
  • Patent number: 10114173
    Abstract: An aspect of the disclosure provides a microring resonator (MRR). Such an MRR includes a ring optical waveguide and an optical waveguide, with the optical waveguide configured such that a first portion of the optical waveguide overlaps a second portion of the ring waveguide. In some embodiments, the optical waveguide has a first refractive index and the ring optical waveguide has a second refractive index such that the first refractive index is less than the second refractive index. In some embodiments, the optical waveguide is a polymer optical waveguide and the ring optical waveguide is a silicon optical waveguide. In some embodiments, the optical waveguide is larger in height than the ring waveguide and the first portion of the optical waveguide is configured to provide space for the second portion of the ring waveguide.
    Type: Grant
    Filed: March 14, 2017
    Date of Patent: October 30, 2018
    Assignee: HUAWEI TECHNOLOGIES CO., LTD.
    Inventors: Chunshu Zhang, Dominic John Goodwill
  • Patent number: 9989406
    Abstract: A calibration system is provided including an aperture layer, a lens layer, an optical filter, a pixel layer and a regulator. The aperture layer defines a calibration aperture. The lens layer includes a calibration lens substantially axially aligned with the calibration aperture. The optical filter is adjacent the lens layer opposite the aperture layer. The pixel layer is adjacent the optical filter opposite the lens layer and includes a calibration pixel substantially axially aligned with the calibration lens. The calibration pixel detects light power of an illumination source that outputs a band of wavelengths of light as a function of a parameter. The regulator modifies the parameter of the illumination source based on a light power detected by the calibration pixel.
    Type: Grant
    Filed: January 30, 2017
    Date of Patent: June 5, 2018
    Assignee: Ouster, Inc.
    Inventors: Angus Pacala, Mark Frichtl
  • Patent number: 9929535
    Abstract: An emitting device is intended for delivering photons with a chosen wavelength. This emitting device includes an InP substrate with a directly modulated laser arranged for generating photons modulated by a non-return-to-zero modulation to produce data to be transmitted, a passive ring resonator monolithically integrated with the directly modulated laser and having a resonance amongst several ones that is used for filtering a zero level induced by the data modulation, and a tuning means arranged along the directly modulated laser and/or around the ring resonator to tune the photon wavelength and/or the ring resonator resonance used for filtering.
    Type: Grant
    Filed: April 15, 2015
    Date of Patent: March 27, 2018
    Assignee: Alcatel Lucent
    Inventors: Nicolas Chimot, Francois Lelarge, Siddharth Joshi
  • Patent number: 9923335
    Abstract: A laser includes a reflective gain medium (RGM) comprising an optical gain material coupled with an associated reflector. The RGM is coupled to a spot-size converter (SSC), which optically couples the RGM to an optical reflector through a silicon waveguide. The SSC converts an optical mode-field size of the RGM to an optical mode-field size of the silicon waveguide. A negative thermo-optic coefficient (NTOC) waveguide is fabricated on top of the SSC. In this way, an optical signal, which originates from the RGM, passes into the SSC, is coupled into the NTOC waveguide, passes through the NTOC waveguide, and is coupled back into the SSC before passing into the silicon waveguide. During operation, the RGM, the spot-size converter, the NTOC waveguide, the silicon waveguide and the silicon mirror collectively form a lasing cavity for the athermal laser. Finally, a laser output is optically coupled to the lasing cavity.
    Type: Grant
    Filed: January 12, 2017
    Date of Patent: March 20, 2018
    Assignee: Oracle International Corporation
    Inventors: Jock T. Bovington, Stevan S. Djordjevic, Xuezhe Zheng, Ashok V. Krishnamoorthy
  • Patent number: 9891500
    Abstract: Systems and methods which provide for the generation of optical frequency combs using a microring resonator optical frequency comb generator configuration are described. A microring resonator optical frequency comb generator configuration of embodiments comprises a plurality of fiber loop laser cavities and at least one microring cavity are utilized. For example, an optical frequency comb generator may include a first fiber loop laser cavity, a second fiber loop laser cavity that is symmetrical with the first fiber loop laser cavity, and a microring resonator that is coupled into both of the first and second fiber loop laser cavities. The microring resonator may be configured to provide a high quality factor, Q, value. The microring resonator of embodiments works together with optical bandpass filters and amplifiers in the multiple fiber loops to make the generated optical frequency comb stable and flexible.
    Type: Grant
    Filed: January 5, 2017
    Date of Patent: February 13, 2018
    Assignee: City University of Hong Kong
    Inventors: Sai Tak Chu, Kun Zhu
  • Patent number: 9863771
    Abstract: An optical rotation sensor is provided, comprising an optical ring resonator (RR) formed by a one-dimensional photonic crystal (1D PhC) waveguide, and a bus waveguide. A light input section of the bus waveguide is connectable to a light source, and a light output section of the bus waveguide is connectable to a light detector. The bus waveguide is optically coupled to the ring resonator within a coupling area which is located between the light input section and the light output section of the bus waveguide. The optical rotation sensor is configured to measure a shift of frequency of a resonance area (or a plurality of resonance areas) close to a band edge of a photonic band gap of the ring resonator, wherein the shift of frequency is caused by a rotation of the optical rotation sensor.
    Type: Grant
    Filed: April 2, 2013
    Date of Patent: January 9, 2018
    Assignee: ESA European Space Agency
    Inventors: Caterina Ciminelli, Edoardo C. Campanella, Mario N. Armenise
  • Patent number: 9829635
    Abstract: An optical interconnector (915) includes: a first vertical coupled cavity (100), a first optical waveguide (102), and a second optical waveguide (103). The first vertical coupled cavity (100) includes N identical micro-resonant cavities that are equidistantly stacked, where a center of each micro-resonant cavity is located on a first straight line that is perpendicular to a plane on which the micro-resonant cavity is located, the first optical waveguide (102) and a first micro-resonant cavity (11) are in a same plane, the second optical waveguide (103) and a second micro-resonant cavity (13) are in a same plane, the first optical waveguide (102) is an input optical waveguide, the second optical waveguide (103) is a first output optical waveguide, and an optical signal having a first resonant wavelength in the first optical waveguide (102) enters the second optical waveguide (103) through the first vertical coupled cavity (100).
    Type: Grant
    Filed: September 27, 2016
    Date of Patent: November 28, 2017
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Xin Tu, Hongyan Fu, Fei Zhao
  • Patent number: 9772187
    Abstract: A ring laser gyroscope (RLG) is provided. The RLG includes a primary resonator, a secondary resonator, and an optical source to provide a pump field. The pump field in the primary resonator stimulates an optical gain curve at a first stokes wave frequency. A first order SBS field stimulates a second optical gain curve at a second stokes wave frequency. The second order SBS gain gives rise to a frequency-shifted field propagating in the first direction. The fraction of the pump field that couples out of the primary resonator, through the secondary resonator, and out of the secondary resonator is larger than the fraction of: the first order SBS field that couples out of the primary resonator, through the secondary resonator, and out of the secondary resonator; and a second order SBS field that couples out of the primary resonator, through the secondary resonator, and out of the secondary resonator.
    Type: Grant
    Filed: February 24, 2016
    Date of Patent: September 26, 2017
    Assignee: Honeywell International Inc.
    Inventors: Mary K. Salit, Jianfeng Wu, Tiequn Qiu
  • Patent number: 9772189
    Abstract: Systems and methods for resonance switching RFOGs with feed-forward processing are provided. In one embodiment, a system comprises: a fiber optic resonator; first and second laser sources coupled to the resonator, wherein the first source launches a first beam into the resonator and the second source launches a second beam into the resonator in an opposite direction; a first servo loop that locks the first beam to a first resonant mode of the resonator during a first state and to a second resonant mode of the resonator during a second state; a second servo loop that locks the second beam to the second resonant mode during the first state and to the first resonant mode during the second state; a feed-forward rate processor coupled to the servo loops that calculates a FSR average across a prior resonance switching cycle of resonant frequency measurements and applies the average to current measurements.
    Type: Grant
    Filed: May 11, 2015
    Date of Patent: September 26, 2017
    Assignee: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Glen A. Sanders, Waymon Ho
  • Patent number: 9702700
    Abstract: A fiber-optic interferometric measurement device (100) intended to measure a physical parameter (QR), includes: a wide-spectrum light source (103); a SAGNAC fiber-optic interferometer (110), in which there propagate two counter-propagating light waves (101, 102) including measurement elements (1140) sensitive to the physical parameter that results in a non-reciprocal phase difference ??? between the two light waves; and a detector (104) delivering an electric signal representative of the physical parameter. The measurement elements include a ring resonator (1143) in transmission mode including a first coupler (1141) and a second coupler (1142) respectively, which couple a first arm (111) and a second arm (112) respectively of the SAGNAC interferometer to the ring resonator, in such a way that the two light waves travel in opposing directions of travel (1143H, 1143AH).
    Type: Grant
    Filed: March 10, 2014
    Date of Patent: July 11, 2017
    Assignee: IXBLUE
    Inventors: Herve Lefevre, Frederic Guattari, Cedric Molucon, Joachin Honthaas, Eric Ducloux, Jean-Jacques Bonnefois
  • Patent number: 9684223
    Abstract: An optical apparatus that includes an optical source that generates a first optical pulse with a first optical wavelength. The optical apparatus also includes an optical amplifier that outputs an amplified pulse. The optical apparatus also includes a first waveguide that is connected to the optical amplifier and a second waveguide. Wherein the second waveguide converts the energy of the amplified pulse into energy of a second pulse that has a second optical wavelength different from the first optical wavelength. Wherein, the following equation is satisfied: L_min?L??/?P. In which a length of the first waveguide is L, a nonlinear coefficient of the first waveguide is ?, a peak power of the amplified pulse as it is received by the first waveguide is P, and a minimum length of the first waveguide is L_min or L is equal to zero.
    Type: Grant
    Filed: February 6, 2015
    Date of Patent: June 20, 2017
    Assignees: Canon Kabushiki Kaisha, ARIZONA BOARD OF REGENTS ON BEHALF OF THE UNIVERSITY OF ARIZONA
    Inventors: Yukihiro Inoue, Dmitry Churin, Khanh Kieu
  • Patent number: 9581448
    Abstract: A method for enhancing a sensitivity of an optical sensor having an optical cavity counter-propagates beams of pump light within the optical cavity to produce scattered light based on Stimulated Brillouin Scattering (SBS). The properties of the pump light are selected to generate fast-light conditions for the scattered light, such that the scattered light includes counter-propagating beams of fast light. The method prevents the pump light from resonating within the optical cavity, while allowing the scattered light to resonate within the optical cavity. At least portions of the scattered light are interfered outside of the optical cavity to produce a beat note for a measurement of the optical sensor. The disclosed method is particularly applicable to optical gyroscopes.
    Type: Grant
    Filed: April 25, 2014
    Date of Patent: February 28, 2017
    Assignee: MagiQ Technologies, Inc.
    Inventors: Caleb A Christensen, Anton Zavriyev
  • Patent number: 9537283
    Abstract: One embodiment is directed towards a stabilized laser including a laser to produce light at a frequency and a resonator coupled to the laser such that the light from the laser circulates therethrough. The laser also includes Pound-Drever-Hall (PDH) feedback electronics configured to adjust the frequency of the light from the laser to reduce phase noise in response to light sensed at the reflection port of the resonator and transmission port feedback electronics configured to adjust the frequency of the light from the laser toward resonance of the resonator at the transmission port in response to the light sensed at the transmission port of the resonator, wherein the transmission port feedback electronics adjust the frequency at a rate at least ten times slower than the PDH feedback electronics.
    Type: Grant
    Filed: November 18, 2014
    Date of Patent: January 3, 2017
    Assignee: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Tiequn Qiu, Glen A. Sanders
  • Patent number: 9537571
    Abstract: A dual-frequency optical source comprises: (a) first and second pump laser sources arranged to generate optical pump power at respective first and second pump laser frequencies vpump1 and vpump2; and (b) a fiber optical resonator characterized by a Brillouin shift frequency vB and a free spectral range that is substantially equal to an integer submultiple of the Brillouin shift frequency. Each one of the first and second pump laser sources is frequency-locked to a corresponding resonant optical mode of the fiber optical resonator. First and second optical output signals of the dual-frequency optical reference source at respective first and second output frequencies v1=vpump1?vB and v2=vpump2?vB comprise stimulated Brillouin laser output generated by simultaneous optical pumping of the fiber optical resonator by the first and second pump laser sources, respectively. An output difference frequency v2?v1 is greater than about 300 GHz.
    Type: Grant
    Filed: January 26, 2015
    Date of Patent: January 3, 2017
    Assignee: CALIFORNIA INSTITUTE OF TECHNOLOGY
    Inventors: Jiang Li, Kerry Vahala
  • Patent number: 9528829
    Abstract: Gyroscopes based on optomechanical designs to provide sensitive sensing while providing relatively large bandwidth and dynamic range with enhanced noise performance.
    Type: Grant
    Filed: July 16, 2012
    Date of Patent: December 27, 2016
    Assignee: CORNELL UNIVERSITY
    Inventors: Sunil Bhave, Renyuan Wang
  • Patent number: 9482535
    Abstract: A system having an optomechanical gyroscope device. An optomechanical disk acts as an optical ring resonator and a mechanical disk resonator. A drive laser generates an optical drive signal. A drive channel acts as a waveguide for the optical drive signal and includes drive electrodes in a first proximity with respect to the optomechanical disk. The drive electrodes to excite the ring by evanescent coupling. A drive photodetector is configured to receive an output optical signal from the drive channel. A sense laser generates a optical sense signal. A sense channel acts as a waveguide for the optical sense signal and includes sense electrodes in a second proximity with respect to the optomechanical disk. A sense photodetector is configured to receive an output optical signal from the sense channel.
    Type: Grant
    Filed: December 23, 2011
    Date of Patent: November 1, 2016
    Assignee: Intel Corporation
    Inventors: John Heck, Haisheng Rong, Richard Jones
  • Patent number: 9389081
    Abstract: A resonator fiber optic gyroscope comprises a master laser that emits a reference optical signal, a first slave laser that emits a first optical signal and is responsive to the reference optical signal through a first optical phase lock loop (OPLL), and a second slave laser that emits a second optical signal and is responsive to the reference optical signal through a second OPLL. A reference resonator in optical communication with the master laser receives the reference optical signal, and comprises a first fiber optic coil having a first cavity length. A gyro resonator, in optical communication with the first and second slave lasers, receives the first and second optical signals. The gyro resonator comprises a second fiber optic coil having a second cavity length longer than the first cavity length. The reference resonator has an operating frequency that substantially tracks with an operating frequency of the gyro resonator.
    Type: Grant
    Filed: April 17, 2015
    Date of Patent: July 12, 2016
    Assignee: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Glen A. Sanders, Tiequn Qiu
  • Patent number: 9354062
    Abstract: Method and apparatus embody a rotation sensor including one or more ring lasers designed to utilize a nonlinear Sagnac effect, a passive waveguide arrangement, and a photodetector arrangement to receive the outcoupled light and to detect rotation of the sensor; wherein these components are arranged into a monolithically integrated optoelectronic integrated circuit on a single substrate. The method and apparatus can include seeding a stable, rotation -insensitive, strong (driving) wave using a single-frequency edge emitting laser monolithically integrated on the same substrate.
    Type: Grant
    Filed: September 16, 2013
    Date of Patent: May 31, 2016
    Assignee: STC.UNM
    Inventors: Marek A. Osinski, Petr G. Eliseev, Edward W. Taylor
  • Patent number: 9354064
    Abstract: A resonator fiber optic gyroscope comprises a master laser device that emits a reference optical signal, a first slave laser device that emits a clockwise optical signal, and a second slave laser device that emits a counter-clockwise optical signal. A resonator ring cavity is in communication with the master laser device and the slave laser devices. A sine wave generator is coupled to the resonator ring cavity and outputs a common cavity modulation frequency comprising in-phase and quadrature signals. A laser stabilization servo receives a clockwise reflection signal that includes the common cavity modulation frequency from the resonator ring cavity. A modulation stripper coupled to the servo receives the in-phase and quadrature signals, receives a net error signal from the servo, demodulates the net error signal at the common cavity modulation frequency, and transmits a stripper signal to the servo to remove the signal at the common cavity modulation frequency.
    Type: Grant
    Filed: July 7, 2014
    Date of Patent: May 31, 2016
    Assignee: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Glen A. Sanders, Jianfeng Wu
  • Patent number: 9212911
    Abstract: A radio frequency based electronic gyroscope function that may be incorporated in its entirety on a monolithic integrated circuit (IC). The detection and measurement of movement in a particular plane is based on the Sagnac effect as it applies to a radio frequency signal that propagates in two different directions in a loop that may be subject to rotational perturbation. In one embodiment, three mutually perpendicular loops that are incorporated into the same integrated circuit and are used to detect and measure movement in three planes (roll, pitch and yaw) thereby allowing a signal processing unit to quantify a general three dimensional movement. The gyroscope can be incorporated into an IC that is used in portable device, such as a mobile handset, to provide it with inertial navigation and movement detection and measurement capabilities.
    Type: Grant
    Filed: September 15, 2014
    Date of Patent: December 15, 2015
    Inventors: Nir Tal, Dan Wolberg, Daryl Wade Barry