Patents by Inventor Josuke Ozaki

Josuke Ozaki 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).

  • Patent number: 10866439
    Abstract: A high-frequency transmission line is provided that improves a high-frequency characteristic. The high-frequency transmission line includes a first conductor line, a termination resistance connected to the first conductor line, a second conductor line connected to the termination resistance, and a ground line that is provided to be opposed to the first conductor line, the termination resistance, and the second conductor line to have a predetermined distance thereto and that is connected to the second conductor line. The first conductor line and the ground line are formed to have a line width decreasing toward the termination resistance, respectively.
    Type: Grant
    Filed: March 23, 2016
    Date of Patent: December 15, 2020
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shigeru Kanazawa, Yuta Ueda, Josuke Ozaki
  • Patent number: 10845668
    Abstract: An IQ optical modulator including: a parent Mach-Zehnder type (MZM) optical waveguide; child MZM optical waveguides constituting two arms of the parent MZM; two electrode transmission lines provided along the two arms of the child MZM, respectively, and receiving modulation signal to phase-modulate an optical signal; an RF extension line connected to the two electrode transmission lines, respectively; a first optical splitter branching light into the two arms of the parent MZM; a second optical splitter branching light into the two arms of the child MZM; and a first optical multiplexer multiplexing light from the two arms of the child MZM, wherein stripe direction of the child MZM optical waveguide is same as the RF extension line, the second optical splitter, and the first optical multiplexer, and is orthogonal to the first optical splitter.
    Type: Grant
    Filed: March 20, 2018
    Date of Patent: November 24, 2020
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yoshihiro Ogiso, Josuke Ozaki, Yuta Ueda
  • Publication number: 20200026145
    Abstract: An IQ optical modulator including: a parent Mach-Zehnder type (MZM) optical waveguide; child MZM optical waveguides constituting two arms of the parent MZM; two electrode transmission lines provided along the two arms of the child MZM, respectively, and receiving modulation signal to phase-modulate an optical signal; an RF extension line connected to the two electrode transmission lines, respectively; a first optical splitter branching light into the two arms of the parent MZM; a second optical splitter branching light into the two arms of the child MZM; and a first optical multiplexer multiplexing light from the two arms of the child MZM, wherein stripe direction of the child MZM optical waveguide is same as the RF extension line, the second optical splitter, and the first optical multiplexer, and is orthogonal to the first optical splitter.
    Type: Application
    Filed: March 20, 2018
    Publication date: January 23, 2020
    Inventors: Yoshihiro Ogiso, Josuke Ozaki, Yuta Ueda
  • Patent number: 10522892
    Abstract: This invention provides a high-frequency line adopting a structure to suppress an impedance variation and occurrence of an excessive power loss in high-frequency wiring having intersection with an optical waveguide. A high-frequency line is a microstrip line which has a basic configuration of stacking a ground electrode, a dielectric layer, and a signal electrode in this order on a SI-InP substrate. In addition, as shown in a transverse sectional view, an optical waveguide core made of InP-based semiconductor intersects with the high-frequency line in a crossing manner. A width of the signal electrode is partially increased in a certain region covering the intersection with the optical waveguide along a propagating direction of the high-frequency line. In the microstrip line, the width of the signal electrode is partially increased from w1 to w2, and characteristic impedance is thus reduced as compared to one with the uniform width w1.
    Type: Grant
    Filed: June 24, 2016
    Date of Patent: December 31, 2019
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Nobuhiro Kikuchi, Eiichi Yamada, Yoshihiro Ogiso, Josuke Ozaki
  • Patent number: 10254624
    Abstract: To provide a Mach-Zehnder (MZ) type semiconductor optical modulation element that can be used as a modulator, which is ultrafast and excellent in electrical stability. A semiconductor optical modulation element of a Mach-Zehnder type that performs modulation of light using a refractive index modulation region where a refractive index of the light guided to an optical waveguide is modulated and an input and output region where multiplexing/demultiplexing of the light split in the refractive index modulation region is performed, characterized in that in the refractive index modulation region of the optical waveguide, an n-type clad layer, an i core layer, and a p-type clad layer are stacked in the order from a top layer on a substrate surface equivalent to a (100) plane of a sphalerite-type seminsulating semiconductor crystal substrate, the n-type clad layer is formed in a ridge shape in an inverted mesa direction, and a capacitancl-oaded electrode is provided on the n-type clad layer.
    Type: Grant
    Filed: June 1, 2016
    Date of Patent: April 9, 2019
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yoshihiro Ogiso, Josuke Ozaki, Norihide Kashio, Nobuhiro Kikuchi, Masaki Kohtoku
  • Publication number: 20180175474
    Abstract: This invention provides a high-frequency line adopting a structure to suppress an impedance variation and occurrence of an excessive power loss in high-frequency wiring having intersection with an optical waveguide. A high-frequency line is a microstrip line which has a basic configuration of stacking a ground electrode, a dielectric layer, and a signal electrode in this order on a SI-InP substrate. In addition, as shown in a transverse sectional view, an optical waveguide core made of InP-based semiconductor intersects with the high-frequency line in a crossing manner. A width of the signal electrode is partially increased in a certain region covering the intersection with the optical waveguide along a propagating direction of the high-frequency line. In the microstrip line, the width of the signal electrode is partially increased from w1 to w2, and characteristic impedance is thus reduced as compared to one with the uniform width w1.
    Type: Application
    Filed: June 24, 2016
    Publication date: June 21, 2018
    Inventors: Nobuhiro Kikuchi, Eiichi Yamada, Yoshihiro Ogiso, Josuke Ozaki
  • Publication number: 20180164654
    Abstract: To provide a Mach-Zehnder (MZ) type semiconductor optical modulation element that can be used as a modulator, which is ultrafast and excellent in electrical stability. A semiconductor optical modulation element of a Mach-Zehnder type that performs modulation of light using a refractive index modulation region where a refractive index of the light guided to an optical waveguide is modulated and an input and output region where multiplexing/demultiplexing of the light split in the refractive index modulation region is performed, characterized in that in the refractive index modulation region of the optical waveguide, an n-type clad layer, an i core layer, and a p-type clad layer are stacked in the order from a top layer on a substrate surface equivalent to a (100) plane of a sphalerite-type semi-insulating semiconductor crystal substrate, the n-type clad layer is formed in a ridge shape in an inverted mesa direction, and a capacitance-loaded electrode is provided on the n-type clad layer.
    Type: Application
    Filed: June 1, 2016
    Publication date: June 14, 2018
    Inventors: Yoshihiro Ogiso, Josuke Ozaki, Norihide Kashio, Nobuhiro Kikuchi, Masaki Kohtoku
  • Publication number: 20180067341
    Abstract: A high-frequency transmission line is provided that improves a high-frequency characteristic. The high-frequency transmission line includes a first conductor line, a termination resistance connected to the first conductor line, a second conductor line connected to the termination resistance, and a ground line that is provided to be opposed to the first conductor line, the termination resistance, and the second conductor line to have a predetermined distance thereto and that is connected to the second conductor line. The first conductor line and the ground line are formed to have a line width decreasing toward the termination resistance, respectively.
    Type: Application
    Filed: March 23, 2016
    Publication date: March 8, 2018
    Inventors: Shigeru Kanazawa, Yuta Ueda, Josuke Ozaki