Patents by Inventor Tiequn Qiu

Tiequn Qiu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20240369776
    Abstract: Techniques are provided for implementing and using a travelling wave resonator. comprising planar optical waveguide including at least two stacked cores, to diminish Kerr effect in the travelling wave resonator. The travelling wave resonator may be used in a resonator optical gyroscope.
    Type: Application
    Filed: July 19, 2024
    Publication date: November 7, 2024
    Applicant: Honeywell International Inc.
    Inventors: Jianfeng Wu, Matthew Wade Puckett, Steven Tin, Tiequn Qiu
  • Publication number: 20240328783
    Abstract: A photonics gyroscope comprises a light source on a photonics chip that emits a broadband beam; a waveguide resonator; a reflective component; first and second detectors, the second detector coupled to the source; a RIN servo loop coupled between the second detector and the source; and a rate calculation unit. The beam is directed into the resonator such that it propagates in a CCW direction. A portion of the CCW beam is coupled out of the resonator toward the reflective component and reflected back as a reflected beam that is coupled into the resonator such that the reflected beam propagates in a CW direction. The CW beam is coupled out of the resonator to the first detector, which detects a resonance frequency shift between the CW and CCW beams. The RIN servo loop stabilizes an intensity of the beam such that bias error and noise is reduced.
    Type: Application
    Filed: March 30, 2023
    Publication date: October 3, 2024
    Applicant: Honeywell International Inc.
    Inventors: Jianfeng Wu, Tiequn Qiu, Matthew Wade Puckett, Steven Tin, Glen A. Sanders
  • Patent number: 12105327
    Abstract: Techniques are provided for implementing and using a travelling wave resonator, comprising planar optical waveguide including at least two stacked cores, to diminish Kerr effect in the travelling wave resonator. The travelling wave resonator may be used in a resonator optical gyroscope.
    Type: Grant
    Filed: December 5, 2022
    Date of Patent: October 1, 2024
    Assignee: Honeywell International Inc.
    Inventors: Jianfeng Wu, Matthew Wade Puckett, Steven Tin, Tiequn Qiu
  • Publication number: 20240302168
    Abstract: A photonics gyroscope comprises a laser and a common intensity modulation unit that outputs an intensity modulated beam, split into a CCW beam having a first power level and a CW beam having a second power level. A first phase modulator (PA) receives the CCW beam, and a second PA receives the CW beam. A variable optical attenuator (VOA) is coupled to the first or second PA. The CCW beam is coupled into a resonator and the CW beam is coupled into the resonator. A first detector receives the CCW beam and a second detector receives the CW beam from the resonator. A CCW control loop locks the CCW beam, and a CW control loop locks the CW beam, to resonance peaks. The VOA receives a feedback loop signal to aid in balancing power levels between CCW and CW beams to eliminate a rate signal at an intensity modulation frequency.
    Type: Application
    Filed: March 10, 2023
    Publication date: September 12, 2024
    Applicant: Honeywell International Inc.
    Inventors: Jianfeng Wu, Tiequn Qiu, Matthew Wade Puckett, Steven Tin
  • Publication number: 20240271936
    Abstract: Techniques are provided for implementing and using a high quality factor travelling wave resonator configured to propagate a transverse magnetic mode optical signals and suppress transverse electric mode optical signals. The travelling wave resonator may be used in a resonator optical gyroscope.
    Type: Application
    Filed: February 9, 2023
    Publication date: August 15, 2024
    Applicant: Honeywell International Inc.
    Inventors: Matthew Wade Puckett, Jianfeng Wu, Steven Tin, Tiequn Qiu
  • Publication number: 20240271937
    Abstract: Techniques are provided for diminishing bias error, in a resonator optical gyroscope, due to an undesired, parasitic optical mode which is orthogonal to a desired optical mode. Energy levels of the undesired, parasitic mode can be diminished utilizing polarizing beam splitters each of which suppresses energy of the undesired, parasitic mode of a clockwise or a counterclockwise optical signal more than energy of the desired mode of the CW optical signal. Optionally, one or more components of a travelling wave resonator system are configured to suppress energy of the undesired, parasitic mode of a clockwise and/or a counterclockwise optical signal more than energy of the desired mode of the respective optical signal(s). Optionally, the desired optical mode is either a transverse magnetic (TM) mode or a transverse electric (TE) mode, and the undesired, parasitic optical mode is respectively the TE mode or the TM mode.
    Type: Application
    Filed: February 9, 2023
    Publication date: August 15, 2024
    Applicant: Honeywell International Inc.
    Inventors: Jianfeng Wu, Tiequn Qiu, Matthew Wade Puckett
  • Publication number: 20240184053
    Abstract: Techniques are provided for implementing and using a travelling wave resonator, comprising planar optical waveguide including at least two stacked cores, to diminish Kerr effect in the travelling wave resonator. The travelling wave resonator may be used in a resonator optical gyroscope.
    Type: Application
    Filed: December 5, 2022
    Publication date: June 6, 2024
    Applicant: Honeywell International Inc.
    Inventors: Jianfeng Wu, Matthew Wade Puckett, Steven Tin, Tiequn Qiu
  • Patent number: 11624614
    Abstract: Systems and methods for reducing rotation sensing errors from laser source signal and modulation cross-talk are provided herein. An RFOG includes a fiber optic resonator; a first laser source that produces a first light wave at a first carrier frequency and a first cross-talked portion at a second carrier frequency wave for propagating in a first direction, wherein a second cross-talked portion propagates in a second direction that is opposite to the first direction; a second laser source that produces a second light wave for propagating in the second direction at a second carrier frequency, and having a third cross-talked portion that propagates in the first direction, a first modulator that modulates the first light wave by suppressing light at the first carrier frequency and the second cross-talked portion at the second carrier frequency, and photodetectors that generate signals from the modulated first light wave and the second light wave.
    Type: Grant
    Filed: August 4, 2020
    Date of Patent: April 11, 2023
    Assignee: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Tiequn Qiu, Glen A. Sanders
  • Publication number: 20230097179
    Abstract: Systems and methods for reducing rotation sensing errors from laser source signal and modulation cross-talk are provided herein. An RFOG includes a fiber optic resonator; a first laser source that produces a first light wave at a first carrier frequency and a first cross-talked portion at a second carrier frequency wave for propagating in a first direction, wherein a second cross-talked portion propagates in a second direction that is opposite to the first direction; a second laser source that produces a second light wave for propagating in the second direction at a second carrier frequency, and having a third cross-talked portion that propagates in the first direction, a first modulator that modulates the first light wave by suppressing light at the first carrier frequency and the second cross-talked portion at the second carrier frequency, and photodetectors that generate signals from the modulated first light wave and the second light wave.
    Type: Application
    Filed: August 4, 2020
    Publication date: March 30, 2023
    Applicant: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Tiequn Qiu, Glen A. Sanders
  • Patent number: 11476633
    Abstract: Systems and methods for ring laser gyroscopes (RLGs) are provided. An RLG includes a traveling-wave resonator cavity with three or more mirrors and a gain medium positioned in the traveling-wave resonator cavity between two of the three or more mirrors. The gain medium is a solid-state gain medium or a nonlinear optical medium. The RLG further includes a first pump laser and a second pump laser to pump the gain medium in different directions and generate first and second lasing signals that traverse the traveling-wave resonator cavity in a opposite directions. The RLG further includes first and second photodetectors to measure levels of the first and second lasing signals. The RLG further includes at least one processor configured to adjust a power level of the first pump laser and/or a power level of the second pump laser based on the measured power levels of the first and second lasing signals.
    Type: Grant
    Filed: July 20, 2020
    Date of Patent: October 18, 2022
    Assignee: Honeywell International Inc.
    Inventors: Tiequn Qiu, Teresa Marta, Jianfeng Wu
  • Publication number: 20220021177
    Abstract: Systems and methods for ring laser gyroscopes (RLGs) are provided. An RLG includes a traveling-wave resonator cavity with three or more mirrors and a gain medium positioned in the traveling-wave resonator cavity between two of the three or more mirrors. The gain medium is a solid-state gain medium or a nonlinear optical medium. The RLG further includes a first pump laser and a second pump laser to pump the gain medium in different directions and generate first and second lasing signals that traverse the traveling-wave resonator cavity in a opposite directions. The RLG further includes first and second photodetectors to measure levels of the first and second lasing signals. The RLG further includes at least one processor configured to adjust a power level of the first pump laser and/or a power level of the second pump laser based on the measured power levels of the first and second lasing signals.
    Type: Application
    Filed: July 20, 2020
    Publication date: January 20, 2022
    Applicant: Honeywell International Inc.
    Inventors: Tiequn Qiu, Teresa Marta, Jianfeng Wu
  • Patent number: 11002545
    Abstract: Systems and methods for performing SHD switching for RFOGS are provided herein. A system includes a resonator in which light resonates; at least one laser source that produces first and second optical beams; heterodyne modulators that modulate the first and second optical beams at a heterodyne frequency plus a modulation frequency offset to produce multiple sideband optical beams, wherein the modulation frequency offset has a different sign for the first and second optical beams; a frequency switching controller that alternatingly switches the signs of the modulation frequency offset applied to the first and second optical beams, wherein the heterodyne modulation of the first and second optical beams are on average at the heterodyne frequency; at least one coupler that couples the sideband optical beams into the resonator; a feedback control that detects the sideband optical beams transmitted from the resonator and, in response, adjusts frequencies of the optical beams.
    Type: Grant
    Filed: August 20, 2019
    Date of Patent: May 11, 2021
    Assignee: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Glen A. Sanders, Jianfeng Wu, Tiequn Qiu, Marc Smiciklas
  • Publication number: 20210055108
    Abstract: Systems and methods for performing SHD switching for RFOGS are provided herein. A system includes a resonator in which light resonates; at least one laser source that produces first and second optical beams; heterodyne modulators that modulate the first and second optical beams at a heterodyne frequency plus a modulation frequency offset to produce multiple sideband optical beams, wherein the modulation frequency offset has a different sign for the first and second optical beams; a frequency switching controller that alternatingly switches the signs of the modulation frequency offset applied to the first and second optical beams, wherein the heterodyne modulation of the first and second optical beams are on average at the heterodyne frequency; at least one coupler that couples the sideband optical beams into the resonator; a feedback control that detects the sideband optical beams transmitted from the resonator and, in response, adjusts frequencies of the optical beams.
    Type: Application
    Filed: August 20, 2019
    Publication date: February 25, 2021
    Applicant: Honeywell International Inc.
    Inventors: Lee K. Strandjord, Glen A. Sanders, Jianfeng Wu, Tiequn Qiu, Marc Smiciklas
  • Patent number: 10914587
    Abstract: Techniques are provided for correcting for time varying changes to a gyroscope incorporating a resonator and/or to an environment in which the gyroscope is located, and which affect the resonator. Free spectral range of the gyroscope, which varies with such changes, is determined and is used to correct at least one of gyroscope bias and scale factor.
    Type: Grant
    Filed: July 23, 2019
    Date of Patent: February 9, 2021
    Assignee: Honeywell International Inc.
    Inventors: Glen A. Sanders, Lee K. Strandjord, Tiequn Qiu, Marc Smiciklas, Norman Gerard Tarleton
  • Publication number: 20210025709
    Abstract: Techniques are provided for correcting for time varying changes to a gyroscope incorporating a resonator and/or to an environment in which the gyroscope is located, and which affect the resonator. Free spectral range of the gyroscope, which varies with such changes, is determined and is used to correct at least one of gyroscope bias and scale factor.
    Type: Application
    Filed: July 23, 2019
    Publication date: January 28, 2021
    Applicant: Honeywell International Inc.
    Inventors: Glen A. Sanders, Lee K. Strandjord, Tiequn Qiu, Marc Smiciklas, Norman Gerard Tarleton
  • Publication number: 20200388984
    Abstract: A micro femtosecond laser with reduced radiation and temperature sensitivity is provided. The laser includes a housing with a radiation shield. Optical components that include a micro gain element are received within the housing. An input end of a pump light delivering fiber is positioned outside the housing. An output end of the pump light delivering fiber is positioned within the housing to deliver input beams to the optical components. A light signal generating pump is used to generate the input beams that are communicated to the input end of the pump light delivering fiber. A first end of a hollow core fiber is positioned within the housing to be in optical communication with the optical components. A second end of the hollow core fiber is positioned outside the housing. A partially reflective output coupling mirror is in optical communication with the second end of the hollow core fiber.
    Type: Application
    Filed: June 7, 2019
    Publication date: December 10, 2020
    Applicant: Honeywell International Inc.
    Inventors: Tiequn Qiu, Chellappan Narayanan, Jeffrey Earl Lewis, Sorin Mosor
  • Publication number: 20200220319
    Abstract: In an example, a mode-locked laser includes a resonator cavity having a saturable absorber, a hollow core fiber coupled to the saturable absorber, and an optical amplifier optically coupled between the hollow core fiber and an output coupler. The mode-locked laser further includes a first pump laser and a wavelength division multiplexer coupled to the first pump laser. The wavelength division multiplexer is configured to couple light from the first pump laser into the resonator cavity to pump the optical amplifier. The mode-locked laser is configured to generate a pulse waveform at a repetition rate of approximately 100 MHz to 200 MHz.
    Type: Application
    Filed: January 9, 2019
    Publication date: July 9, 2020
    Applicant: Honeywell International Inc.
    Inventors: Chellappan Narayanan, Jeffrey Earl Lewis, Sorin Mosor, Tiequn Qiu
  • Patent number: 10627654
    Abstract: An acousto-optic waveguide device comprises a substrate comprising a first material having a first refractive index and a first acoustic velocity; a cladding layer over the substrate, the cladding layer comprising a second material having a second refractive index that is distinct from the first refractive index, the second material having a second acoustic velocity that is distinct from the first acoustic velocity; and an optical core surrounded by the cladding layer, the optical core comprising a third material having a third refractive index that is higher that the first refractive index and the second refractive index, the third material having a third acoustic velocity that is distinct from the first acoustic velocity and the second acoustic velocity. The cladding layer that surrounds the optical core has a thickness configured to substantially confine acoustic waves to the cladding layer when an optical signal propagates through the optical core.
    Type: Grant
    Filed: March 18, 2019
    Date of Patent: April 21, 2020
    Assignee: Honeywell International Inc.
    Inventors: Matthew Wade Puckett, Jianfeng Wu, Mary Salit, Tiequn Qiu
  • Publication number: 20200096698
    Abstract: An acousto-optic waveguide device comprises a substrate comprising a first material having a first refractive index and a first acoustic velocity; a cladding layer over the substrate, the cladding layer comprising a second material having a second refractive index that is distinct from the first refractive index, the second material having a second acoustic velocity that is distinct from the first acoustic velocity; and an optical core surrounded by the cladding layer, the optical core comprising a third material having a third refractive index that is higher that the first refractive index and the second refractive index, the third material having a third acoustic velocity that is distinct from the first acoustic velocity and the second acoustic velocity. The cladding layer that surrounds the optical core has a thickness configured to substantially confine acoustic waves to the cladding layer when an optical signal propagates through the optical core.
    Type: Application
    Filed: March 18, 2019
    Publication date: March 26, 2020
    Applicant: Honeywell International Inc.
    Inventors: Matthew Wade Puckett, Jianfeng Wu, Mary Salit, Tiequn Qiu
  • Publication number: 20200072609
    Abstract: A method is provided. The method comprises: receiving a first optical signal and a second optical signal; injecting the first optical signal into an optical resonator so that the first optical signal propagates in a first direction through the optical resonator; injecting the second optical signal into the optical resonator so that the second optical signal propagates in a second direction through the optical resonator, which is opposite to the first direction; filtering an optical signal propagating in the first direction of the optical resonator with a first common polarizer having the first polarization; and filtering an optical signal propagating in the second direction of the optical resonator with the first common polarizer.
    Type: Application
    Filed: September 4, 2018
    Publication date: March 5, 2020
    Applicant: Honeywell International Inc.
    Inventors: Neil A. Krueger, Tiequn Qiu, Lee K. Strandjord, Glen A. Sanders