Patents by Inventor Shusaku Hayashi

Shusaku Hayashi 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: 20210181427
    Abstract: A grating coupler having first and second ends for coupling a light beam to a waveguide of a chip includes a substrate configured to receive the light beam from the first end and transmit the light beam through the second end, the substrate having a first refractive index n1, a grating structure having curved grating lines arranged on the substrate, the grating structure having a second refractive index n1, wherein the curved grating lines have line width w and height d and are arranged by a pitch ?, wherein the second refractive index n2 is less than first refractive index n1, and a cladding layer configured to cover the grating structure, wherein the cladding layer has a third refractive index n3. The curves of the grating lines are constructed such that the emitting beam is shaped for efficient coupling to another optical component. The curves can also be tilted to reduce coupling back into the waveguide.
    Type: Application
    Filed: February 23, 2021
    Publication date: June 17, 2021
    Applicants: Mitsubishi Electric Research Laboratories, Inc., Mitsubishi Electric Corporation
    Inventors: Keisuke Kojima, Satoshi Nishikawa, Shusaku Hayashi, Yosuke Suzuki, Jonathan Klamkin, Yingheng Tang
  • Publication number: 20210116645
    Abstract: A grating coupler having first and second ends for coupling a light beam to a waveguide of a chip includes a substrate configured to receive the light beam from the first end and transmit the light beam through the second end, the substrate having a first refractive index n1, a grating structure having curved grating lines arranged on the substrate, the grating structure having a second refractive index n1, wherein the curved grating lines have line width w and height d and are arranged by a pitch ?, wherein the second refractive index n2 is less than first refractive index n1, and a cladding layer configured to cover the grating structure, wherein the cladding layer has a third refractive index n3. The curves of the grating lines are constructed such that the emitting beam is shaped for efficient coupling to another optical component. The curves can also be tilted to reduce coupling back into the waveguide.
    Type: Application
    Filed: January 28, 2020
    Publication date: April 22, 2021
    Applicants: Mitsubishi Electric Research Laboratories, Inc., Mitsubishi Electric Corporation
    Inventors: Keisuke Kojima, Satoshi Nishikawa, Shusaku Hayashi, Yosuke Suzuki, Jonathan Klamkin, Yingheng Tang
  • Patent number: 10899188
    Abstract: A coil spring includes a wire shaped to be helical, and is compressed between an upper spring seat and a lower spring seat. The coil spring includes an upper portion and a lower portion. A positive pitch winding end portion is formed on the upper portion of the coil spring. A terminal-point-strong-abutting-portion is formed at a distal end of the winding end portion. The terminal-point-strong-abutting-portion is in contact with the upper spring seat at one point at a position deviated to an inner side of a vehicle with respect to a coil central axis. On the lower portion of the coil spring, an end turn portion which contacts the lower spring seat is formed.
    Type: Grant
    Filed: February 25, 2020
    Date of Patent: January 26, 2021
    Assignee: NHK SPRING CO., LTD.
    Inventors: Ken Okura, Shuji Ohmura, Shusaku Hayashi
  • Patent number: 10805009
    Abstract: An optical modulation apparatus that can adjust modulation timing. A timing adjuster adjusts the modulation timing on the basis of an intensity detected by a light intensity detector, after a data generator respectively generates, as a first data signal and a second data signal, a first test data signal and a second test data signal each having a data string containing a test pattern in which a plurality of continuous marks and a plurality of continuous spaces are alternately repeated, and after a phase adjuster adjusts a phase difference to zero or ?.
    Type: Grant
    Filed: May 22, 2017
    Date of Patent: October 13, 2020
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Shusaku Hayashi, Kentaro Enoki, Koichi Akiyama
  • Publication number: 20200225556
    Abstract: A semiconductor optical modulator includes a modulation region and a non-modulation region. A first width of a first ground electrode in the non-modulation region is larger than a second width of the first ground electrode in the modulation region. A third width of a second ground electrode in the non-modulation region is larger than a fourth width of the second ground electrode in the modulation region. In the non-modulation region, a first insulating layer is disposed between a first optical waveguide and a first traveling wave electrode and between a second optical waveguide and a second traveling wave electrode. For this reason, a bandwidth of the semiconductor optical modulator can be widened.
    Type: Application
    Filed: August 9, 2018
    Publication date: July 16, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventors: Shusaku HAYASHI, Koichi AKIYAMA
  • Publication number: 20200189343
    Abstract: A coil spring includes a wire shaped to be helical, and is compressed between an upper spring seat and a lower spring seat. The coil spring includes an upper portion and a lower portion. A positive pitch winding end portion is formed on the upper portion of the coil spring. A terminal-point-strong-abutting-portion is formed at a distal end of the winding end portion. The terminal-point-strong-abutting-portion is in contact with the upper spring seat at one point at a position deviated to an inner side of a vehicle with respect to a coil central axis. On the lower portion of the coil spring, an end turn portion which contacts the lower spring seat is formed.
    Type: Application
    Filed: February 25, 2020
    Publication date: June 18, 2020
    Applicant: NHK SPRING CO., LTD.
    Inventors: Ken OKURA, Shuji OHMURA, Shusaku HAYASHI
  • Patent number: 10547389
    Abstract: A timing adjuster shifts a timing between a first data-stream group and a second data-stream group in accordance with a timing setting. A data generator in first test mode generates a first test-data stream repeating 2N-bit marks and 2N-bit spaces as each of a first data stream and a third data stream, and generates a second test-data stream that is N-bit shifted from the first test-data stream, where N denotes a natural number. A first phase-difference setting and a second phase-difference setting are rendered zero. The timing adjuster adjusts the timing setting so as to maximize a detected value from a peak detection circuit.
    Type: Grant
    Filed: May 18, 2017
    Date of Patent: January 28, 2020
    Assignee: Mitsubishi Electric Corporation
    Inventors: Shusaku Hayashi, Kentaro Enoki, Koichi Akiyama
  • Publication number: 20190229810
    Abstract: An optical modulation apparatus that can adjust modulation timing. A timing adjuster adjusts the modulation timing on the basis of an intensity detected by a light intensity detector, after a data generator respectively generates, as a first data signal and a second data signal, a first test data signal and a second test data signal each having a data string containing a test pattern in which a plurality of continuous marks and a plurality of continuous spaces are alternately repeated, and after a phase adjuster adjusts a phase difference to zero or ?.
    Type: Application
    Filed: May 22, 2017
    Publication date: July 25, 2019
    Applicant: Mitsubishi Electric Corporation
    Inventors: Shusaku HAYASHI, Kentaro ENOKI, Koichi AKIYAMA
  • Publication number: 20190165862
    Abstract: A timing adjuster shifts a timing between a first data-stream group and a second data-stream group in accordance with a timing setting. A data generator in first test mode generates a first test-data stream repeating 2N-bit marks and 2N-bit spaces as each of a first data stream and a third data stream, and generates a second test-data stream that is N-bit shifted from the first test-data stream, where N denotes a natural number. A first phase-difference setting and a second phase-difference setting are rendered zero. The timing adjuster adjusts the timing setting so as to maximize a detected value from a peak detection circuit.
    Type: Application
    Filed: May 18, 2017
    Publication date: May 30, 2019
    Applicant: Mitsubishi Electric Corporation
    Inventors: Shusaku HAYASHI, Kentaro ENOKI, Koichi AKIYAMA
  • Patent number: 10200130
    Abstract: An optical transmitter includes: a splitter; a first optical modulator and a second optical modulator that modulate each of light beams split by the splitter; a first semiconductor optical amplifier (SOA) and a second SOA that are connected to a subsequent stage of the first optical modulator and a subsequent stage of the second optical modulator, respectively; a first detector and a second detector that detect light output intensity of the first SOA and light output intensity of the second SOA, respectively; a controller that sets gains of the first and second SOAs such that the first and second SOAs are equal in the light output intensity based on detection values of the first and second detectors; and a combiner that combines an output light beam of the first SOA and an output light beam of the second SOA.
    Type: Grant
    Filed: January 27, 2017
    Date of Patent: February 5, 2019
    Assignee: Mitsubishi Electric Corporation
    Inventors: Shusaku Hayashi, Satoshi Nishikawa, Koichi Akiyama, Eiji Yagyu
  • Publication number: 20180215227
    Abstract: A coil spring includes a wire formed of spring steel shaped to be helical, and is compressed between an upper spring seat and a lower spring seat. The coil spring includes an upper portion and a lower portion. A positive pitch winding end portion is formed on the upper portion of the coil spring. A terminal-point-strong-abutting-portion is formed at a distal end of the winding end portion. The terminal-point-strong-abutting-portion is in contact with the upper spring seat at one point at a position deviated to an inner side of a vehicle with respect to a coil central axis. On the lower portion of the coil spring, an end turn portion which contacts the lower spring seat is formed at a position deviated to an outer side of the vehicle.
    Type: Application
    Filed: March 27, 2018
    Publication date: August 2, 2018
    Applicant: NHK SPRING CO., LTD.
    Inventors: Ken OKURA, Shuji OHMURA, Shusaku HAYASHI
  • Patent number: 9989830
    Abstract: An optical modulator element includes first and second optical modulators, an optical input terminal, and a branch coupler. Each of the first and second optical modulators includes a pair of Mach-Zehnder waveguides, a first optical coupler to split rays from the branch coupler into the pair of Mach-Zehnder waveguides, and a second optical coupler to combine rays transmitted through the pair of Mach-Zehnder waveguides. The first and second optical modulators are disposed in such a manner that a traveling direction of rays propagating through the pair of Mach-Zehnder waveguides of the first optical modulator and a traveling direction of rays propagating through the pair of Mach-Zehnder waveguides of the second optical modulator are angled toward each other.
    Type: Grant
    Filed: February 6, 2017
    Date of Patent: June 5, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yuichiro Horiguchi, Satoshi Nishikawa, Koichi Akiyama, Shusaku Hayashi, Yohei Hokama, Kentaro Enoki, Toshiyuki Tanaka
  • Patent number: 9768886
    Abstract: An optical receiver including: a phase modulation unit that generates local oscillation light and modulates a phase of the local oscillation light; a coherent detection unit that causes a received optical signal and the local oscillation light phase-modulated by the phase modulation unit to interfere and converts the optical signal to an electrical signal; a polarization separation/adaptive equalization unit that performs polarization separation and adaptive equalization on the electrical signal after coherent detection; and decoding units that decode the polarization-separated electrical signals outputted from the polarization separation/adaptive equalization unit.
    Type: Grant
    Filed: February 13, 2014
    Date of Patent: September 19, 2017
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Mitsuko Mieno, Tsuyoshi Yoshida, Hiroaki Shintaku, Shusaku Hayashi
  • Publication number: 20170244491
    Abstract: An optical transmitter includes: a splitter; a first optical modulator and a second optical modulator that modulate each of light beams split by the splitter; a first semiconductor optical amplifier (SOA) and a second SOA that are connected to a subsequent stage of the first optical modulator and a subsequent stage of the second optical modulator, respectively; a first detector and a second detector that detect light output intensity of the first SOA and light output intensity of the second SOA, respectively; a controller that sets gains of the first and second SOAs such that the first and second SOAs are equal in the light output intensity based on detection values of the first and second detectors; and a combiner that combines an output light beam of the first SOA and an output light beam of the second SOA.
    Type: Application
    Filed: January 27, 2017
    Publication date: August 24, 2017
    Applicant: Mitsubishi Electric Corporation
    Inventors: Shusaku HAYASHI, Satoshi NISHIKAWA, Koichi AKIYAMA, Eiji YAGYU
  • Publication number: 20170242316
    Abstract: An optical modulator element includes first and second optical modulators, an optical input terminal, and a branch coupler. Each of the first and second optical modulators includes a pair of Mach-Zehnder waveguides, a first optical coupler to split rays from the branch coupler into the pair of Mach-Zehnder waveguides, and a second optical coupler to combine rays transmitted through the pair of Mach-Zehnder waveguides. The first and second optical modulators are disposed in such a manner that a traveling direction of rays propagating through the pair of Mach-Zehnder waveguides of the first optical modulator and a traveling direction of rays propagating through the pair of Mach-Zehnder waveguides of the second optical modulator are angled toward each other.
    Type: Application
    Filed: February 6, 2017
    Publication date: August 24, 2017
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yuichiro HORIGUCHI, Satoshi NISHIKAWA, Koichi AKIYAMA, Shusaku HAYASHI, Yohei HOKAMA, Kentaro ENOKI, Toshiyuki TANAKA
  • Patent number: 9735878
    Abstract: An optical modulation unit included in an optical transmitter includes two optical modulators that modulate each of two light beams based on applied bias voltages and input modulation signals, and an optical phase regulator that is connected to either of the two optical modulators, and regulates a phase of the light beam incident on the optical modulator. In a state where no modulation signal is input to the two optical modulators, while keeping bias voltages to be applied to one optical modulator and the optical phase regulator constant, the controller determines a first initial bias voltage such that an output light beam from the other optical modulator becomes zero. Thereafter, the controller determines a second initial bias voltage such that an output light beam from the one optical modulator becomes zero, while applying the first initial bias voltage to the other optical modulator.
    Type: Grant
    Filed: December 3, 2014
    Date of Patent: August 15, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kentaro Enoki, Yasuhisa Shimakura, Eiji Yagyu, Hiroaki Shintaku, Shusaku Hayashi
  • Publication number: 20160337044
    Abstract: An optical receiver including: a phase modulation unit that generates local oscillation light and modulates a phase of the local oscillation light; a coherent detection unit that causes a received optical signal and the local oscillation light phase-modulated by the phase modulation unit to interfere and converts the optical signal to an electrical signal; a polarization separation/adaptive equalization unit that performs polarization separation and adaptive equalization on the electrical signal after coherent detection; and decoding units that decode the polarization-separated electrical signals outputted from the polarization separation/adaptive equalization unit.
    Type: Application
    Filed: February 13, 2014
    Publication date: November 17, 2016
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Mitsuko MIENO, Tsuyoshi YOSHIDA, Hiroaki SHINTAKU, Shusaku HAYASHI
  • Publication number: 20160254862
    Abstract: A wavelength multiplexing transmission system including an optical transmission and reception device including a plurality of transponders each having a plurality of optical transmitters and receivers, a BER monitoring device to monitor the BERs of the optical transmitters and receivers, variable optical attenuators to attenuate light signals outputted from the optical transmitters and receivers, a controller to control the amounts of attenuation of the variable optical attenuators such that the sum total of the BERs of the optical transmitters and receivers becomes small, and an optical multiplexing and demultiplexing device to multiplex the light signals attenuated into a light signal and transmit this light signal to outside the system, and demultiplex a light signal from outside the system into light signals and transmit these light signals to the optical transmitters and receivers.
    Type: Application
    Filed: November 20, 2014
    Publication date: September 1, 2016
    Applicant: MITSUBISH ELECTRIC CORPORATION
    Inventor: Shusaku HAYASHI
  • Publication number: 20150171971
    Abstract: An optical modulation unit included in an optical transmitter includes two optical modulators that modulate each of two light beams based on applied bias voltages and input modulation signals, and an optical phase regulator that is connected to either of the two optical modulators, and regulates a phase of the light beam incident on the optical modulator. In a state where no modulation signal is input to the two optical modulators, while keeping bias voltages to be applied to one optical modulator and the optical phase regulator constant, the controller determines a first initial bias voltage such that an output light beam from the other optical modulator becomes zero. Thereafter, the controller determines a second initial bias voltage such that an output light beam from the one optical modulator becomes zero, while applying the first initial bias voltage to the other optical modulator.
    Type: Application
    Filed: December 3, 2014
    Publication date: June 18, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kentaro ENOKI, Yasuhisa Shimakura, Eiji Yagyu, Hiroaki Shintaku, Shusaku Hayashi
  • Publication number: 20120230679
    Abstract: An optical transmitter includes: a data generating unit configured to generate a plurality of modulating signals; a driver configured to amplify the plurality of modulating signals generated by the data generating unit; a phase shifter configured to control a phase of at least one signal among the plurality of modulating signals to be input to the driver; a plurality of optical modulators connected in series to each other, and configured to modulate an optical signal on a basis of each of the modulating signals amplified by the driver; an optical coupler configured to branch the optical signal modulated by the optical modulator arranged at a last stage in the series; a photodiode configured to detect the optical signal branched by the optical coupler and convert the optical signal into an electric signal; and a phase control unit configured to control an amount of phase control of the phase shifter to maximize an intensity of the electric signal converted by the photodiode.
    Type: Application
    Filed: February 22, 2010
    Publication date: September 13, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Shusaku Hayashi, Yasuhisa Shimakura, Kazushige Sawada