Patents by Inventor Yoshihiko Yoshida

Yoshihiko Yoshida 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: 20230161184
    Abstract: An optical device includes a substrate, a first cladding layer that is laminated on one surface of the substrate, and a first optical waveguide that is formed in the first cladding layer at a side opposite to the substrate in the first cladding layer. The optical device further includes an electro-optic crystal layer that is laminated on a surface of the first cladding layer at a side opposite to the substrate, and a second optical waveguide that is formed of the electro-optic crystal layer on a surface of the electro-optic crystal layer at a side opposite to the first cladding layer. The optical device further includes a second cladding layer that is laminated on a surface of the electro-optic crystal layer at a side opposite to the first cladding layer.
    Type: Application
    Filed: September 19, 2022
    Publication date: May 25, 2023
    Applicant: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Shuntaro MAKINO, Teruo KURAHASHI, Yoshinobu KUBOTA, Yoshihiko YOSHIDA, Nobuaki MITAMURA, Takehito TANAKA
  • Publication number: 20230004028
    Abstract: An optical device includes a thin film Lithium Niobate (LN) layer, a first optical waveguide, and a second optical waveguide. The thin film LN layer is an X-cut or a Y-cut LN layer. The first optical waveguide is an optical waveguide that is formed on the thin film LN layer along a direction that is substantially perpendicular to a Z direction of a crystal axis of the thin film LN layer. The second optical waveguide is an optical waveguide that is routed and connected to the first optical waveguide. At least a part of a core of the first optical waveguide is made thicker than a core of the second optical waveguide.
    Type: Application
    Filed: April 21, 2022
    Publication date: January 5, 2023
    Applicant: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Shuntaro MAKINO, Yoshinobu KUBOTA, Yasuhiro OHMORI, Masaharu DOI, Masaki SUGIYAMA, Shintaro TAKEUCHI, Yoshihiko YOSHIDA, Shinji MARUYAMA, Teruo KURAHASHI
  • Publication number: 20220390775
    Abstract: An optical device includes an X-cut substrate, and a first waveguide and a second waveguide each being formed on the substrate and having a folding structure. The optical device includes a first signal electrode to generate a first electric field, and a second signal electrode to generate a second electric field with a reverse phase as compared to the first field. The first waveguide includes a first waveguide on an outward side to which the first field is applied from the first signal electrode, and a first waveguide on a return side to which the second field is applied from the second signal electrode. The second waveguide includes a second waveguide on the outward side to which the first field is applied from the first signal electrode, and a second waveguide on the return side to which the second field is applied from the second signal electrode.
    Type: Application
    Filed: April 21, 2022
    Publication date: December 8, 2022
    Applicant: Fujitsu Optical Components Limited
    Inventors: Shuntaro Makino, Masaharu Doi, YOSHIHIKO YOSHIDA
  • Publication number: 20220373828
    Abstract: An optical device includes a silicon substrate, a waveguide formed of a thin film that is laminated on the silicon substrate and that is made of a perovskite oxide with a large electro-optic effect as compared to lithium niobate, and a cladding layer that covers the waveguide. Further, the optical device includes ground electrode that has a ground potential and a signal electrode that is arranged at a position facing the ground electrode and that applies driving voltage to the waveguide.
    Type: Application
    Filed: March 21, 2022
    Publication date: November 24, 2022
    Applicant: Fujitsu Optical Components Limited
    Inventors: YOSHIHIKO YOSHIDA, NOBUAKI MITAMURA, Shuntaro Makino, Yoshinobu Kubota
  • Patent number: 11086149
    Abstract: An electro-optic device is provided with a substrate, an optical waveguide formed of a lithium niobate film with a ridge shape on the substrate, and an electrode that applies an electric field to the optical waveguide. The optical waveguide includes a first waveguide section provided at least in an electric field application region applied with the electric field and having a thickness of 1 ?m or larger and a second waveguide section provided in a region other than the electric field application region and having a thickness of 0.3 ?m or larger and less than 1 ?m.
    Type: Grant
    Filed: March 27, 2020
    Date of Patent: August 10, 2021
    Assignees: TDK CORPORATION, FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Shinji Iwatsuka, Kenji Sasaki, Hiroki Hara, Yasuhiro Ohmori, Masaharu Doi, Shintaro Takeuchi, Yoshihiko Yoshida, Yoshinobu Kubota
  • Publication number: 20210103165
    Abstract: An electro-optic device is provided with a substrate, an optical waveguide formed of a lithium niobate film with a ridge shape on the substrate, and an electrode that applies an electric field to the optical waveguide. The optical waveguide includes a modulation waveguide provided in an electric field application region applied with the electric field and having a thickness of 1 ?m or larger and a bent waveguide provided in a region other than the electric field application region and having a curvature radius of 16 ?m or larger and 80 ?m or smaller.
    Type: Application
    Filed: March 27, 2020
    Publication date: April 8, 2021
    Inventors: Shinji IWATSUKA, Kenji SASAKI, Hiroki HARA, Yasuhiro OHMORI, Masaharu DOI, Shintaro TAKEUCHI, Yoshihiko YOSHIDA, Yoshinobu KUBOTA
  • Publication number: 20200310216
    Abstract: An electro-optic device is provided with a substrate, an optical waveguide formed of a lithium niobate film with a ridge shape on the substrate, and an electrode that applies an electric field to the optical waveguide. The optical waveguide includes a first waveguide section provided at least in an electric field application region applied with the electric field and having a thickness of 1 ?m or larger and a second waveguide section provided in a region other than the electric field application region and having a thickness of 0.3 ?m or larger and less than 1 ?m.
    Type: Application
    Filed: March 27, 2020
    Publication date: October 1, 2020
    Inventors: Shinji IWATSUKA, Kenji SASAKI, Hiroki HARA, Yasuhiro OHMORI, Masaharu DOI, Shintaro TAKEUCHI, Yoshihiko YOSHIDA, Yoshinobu KUBOTA
  • Patent number: 10754179
    Abstract: An optical modulator includes an optical waveguide of a ridge type formed of a thin film of a dielectric material having an electro-optic effect over a substrate, a buffer layer covering the optical waveguide, and a signal electrode provided over the optical waveguide via the buffer layer, wherein a width of the signal electrode is greater than a ridge width of the optical waveguide and wherein the signal electrode covers at least one of sidewalls of a ridge of the optical waveguide.
    Type: Grant
    Filed: July 18, 2019
    Date of Patent: August 25, 2020
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Yasuhiro Ohmori, Yoshinobu Kubota, Masaharu Doi, Shintaro Takeuchi, Yoshihiko Yoshida
  • Publication number: 20200041824
    Abstract: An optical modulator includes an optical waveguide of a ridge type formed of a thin film of a dielectric material having an electro-optic effect over a substrate, a buffer layer covering the optical waveguide, and a signal electrode provided over the optical waveguide via the buffer layer, wherein a width of the signal electrode is greater than a ridge width of the optical waveguide and wherein the signal electrode covers at least one of sidewalls of a ridge of the optical waveguide.
    Type: Application
    Filed: July 18, 2019
    Publication date: February 6, 2020
    Applicant: Fujitsu Optical Components Limited
    Inventors: Yasuhiro OHMORI, Yoshinobu KUBOTA, Masaharu DOI, Shintaro TAKEUCHI, Yoshihiko YOSHIDA
  • Patent number: 10303036
    Abstract: An optical modulator includes a substrate and an optical waveguide group. The optical waveguide group includes a pair of relay optical waveguides, a pair of first Mach-Zehnder type optical waveguides, and a pair of second Mach-Zehnder type optical waveguides. The pair of the first Mach-Zehnder type optical waveguides are connected to the pair of the relay optical waveguides and includes input ends arranged at positions that deviate from each other in a longitudinal direction of the substrate. The pair of the second Mach-Zehnder type optical waveguides are provided on a pair of branched waveguides of each of the first Mach-Zehnder type optical waveguides and includes input ends arranged at symmetric positions with respect to a straight line that passes through an input end serving as a branch point of the branched waveguides and that extends in the longitudinal direction of the substrate.
    Type: Grant
    Filed: July 12, 2017
    Date of Patent: May 28, 2019
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Shintaro Takeuchi, Yoshihiko Yoshida, Yoshinobu Kubota, Masaharu Doi, Yasuhiro Ohmori
  • Patent number: 10281748
    Abstract: An optical modulator includes a substrate having an electro-optic effect; a waveguide pattern provided on the substrate and configured to modulate light; and a dummy pattern having a predetermined potential along the waveguide pattern from an input side to an output side.
    Type: Grant
    Filed: October 10, 2017
    Date of Patent: May 7, 2019
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Toyokazu Sasaki, Yoshihiko Yoshida, Yasuhiro Ohmori, Yoshinobu Kubota
  • Patent number: 10082683
    Abstract: An optical modulator includes: a ferroelectric substrate in which an input optical waveguide, a pair of branched optical waveguides, and an output optical waveguide are formed; a signal electrode that is formed in a vicinity of at least one of the pair of branched optical waveguides; a first protection member that is attached to an input end of the ferroelectric substrate in which the input optical waveguide is formed; and a second protection member that is attached to an output end of the ferroelectric substrate in which the output optical waveguide is formed. The first protection member and the second protection member have a Mohs hardness that is less than or equal to a Mohs hardness of the ferroelectric substrate, and are formed of a glass material that does not have a pyroelectric effect.
    Type: Grant
    Filed: June 8, 2017
    Date of Patent: September 25, 2018
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Yoshihiko Yoshida, Masaharu Doi, Yoshinobu Kubota
  • Publication number: 20180129083
    Abstract: An optical modulator includes a substrate having an electro-optic effect; a waveguide pattern provided on the substrate and configured to modulate light; and a dummy pattern having a predetermined potential along the waveguide pattern from an input side to an output side.
    Type: Application
    Filed: October 10, 2017
    Publication date: May 10, 2018
    Applicant: Fujitsu Optical Components Limited
    Inventors: Toyokazu SASAKI, Yoshihiko YOSHIDA, Yasuhiro OHMORI, Yoshinobu KUBOTA
  • Publication number: 20180081251
    Abstract: An optical modulator includes a substrate and an optical waveguide group. The optical waveguide group includes a pair of relay optical waveguides, a pair of first Mach-Zehnder type optical waveguides, and a pair of second Mach-Zehnder type optical waveguides. The pair of the first Mach-Zehnder type optical waveguides are connected to the pair of the relay optical waveguides and includes input ends arranged at positions that deviate from each other in a longitudinal direction of the substrate. The pair of the second Mach-Zehnder type optical waveguides are provided on a pair of branched waveguides of each of the first Mach-Zehnder type optical waveguides and includes input ends arranged at symmetric positions with respect to a straight line that passes through an input end serving as a branch point of the branched waveguides and that extends in the longitudinal direction of the substrate.
    Type: Application
    Filed: July 12, 2017
    Publication date: March 22, 2018
    Applicant: Fujitsu Optical Components Limited
    Inventors: Shintaro TAKEUCHI, YOSHIHIKO YOSHIDA, Yoshinobu Kubota, Masaharu Doi, Yasuhiro Ohmori
  • Publication number: 20180031869
    Abstract: An optical modulator includes: a ferroelectric substrate in which an input optical waveguide, a pair of branched optical waveguides, and an output optical waveguide are formed; a signal electrode that is formed in a vicinity of at least one of the pair of branched optical waveguides; a first protection member that is attached to an input end of the ferroelectric substrate in which the input optical waveguide is formed; and a second protection member that is attached to an output end of the ferroelectric substrate in which the output optical waveguide is formed. The first protection member and the second protection member have a Mohs hardness that is less than or equal to a Mohs hardness of the ferroelectric substrate, and are formed of a glass material that does not have a pyroelectric effect.
    Type: Application
    Filed: June 8, 2017
    Publication date: February 1, 2018
    Applicant: Fujitsu Optical Components Limited
    Inventors: YOSHIHIKO YOSHIDA, Masaharu Doi, Yoshinobu Kubota
  • Publication number: 20170017097
    Abstract: An optical modulator includes: a ferroelectric substrate in which an input optical waveguide, first and second optical waveguides, and an output optical waveguide are formed; a first electrode formed in a vicinity of the first optical waveguide and to which a first DC voltage is applied; a second electrode formed in a vicinity of the second optical waveguide and to which a second DC voltage is applied; a third electrode electrically connected to the first electrode and formed on both sides of the second electrode; and a fourth electrode electrically connected to the second electrode and formed on both sides of the first electrode. A first gap between the first electrode and the fourth electrode is approximately the same as a second gap between the second electrode and the third electrode. A gap between the third electrode and the fourth electrode is 1-5 times greater than the first gap.
    Type: Application
    Filed: September 29, 2016
    Publication date: January 19, 2017
    Applicant: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Masaharu DOI, Yoshihiko YOSHIDA, Yoshinobu KUBOTA, Yoshitada KAWASHIMA
  • Publication number: 20160223881
    Abstract: An optical modulator includes: a ferroelectric substrate in which an input optical waveguide, first and second optical waveguides, and an output optical waveguide are formed; a first electrode formed in a vicinity of the first optical waveguide and to which a first DC voltage is applied; a second electrode formed in a vicinity of the second optical waveguide and to which a second DC voltage is applied; a third electrode electrically connected to the first electrode and formed on both sides of the second electrode; and a fourth electrode electrically connected to the second electrode and formed on both sides of the first electrode. A first gap between the first electrode and the fourth electrode is approximately the same as a second gap between the second electrode and the third electrode. A gap between the third electrode and the fourth electrode is 1-5 times greater than the first gap.
    Type: Application
    Filed: November 19, 2015
    Publication date: August 4, 2016
    Applicant: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Masaharu DOI, YOSHIHIKO YOSHIDA, Yoshinobu KUBOTA, Yoshitada KAWASHIMA
  • Patent number: 9335490
    Abstract: An optical device includes a substrate having an electrooptical effect, and including an optical waveguide that guides light and a reflection groove having a bottom face that reflects light output from the optical waveguide; and a light-receiving element positioned above the reflection groove and fixed to the substrate. The light output from the optical waveguide into the reflection groove is reflected by the bottom face of the reflection groove while traveling through a space inside the reflection groove and is incident to the light-receiving element.
    Type: Grant
    Filed: July 11, 2014
    Date of Patent: May 10, 2016
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Shinji Maruyama, Yoshihiko Yoshida, Tomoyuki Ito, Yoshihiro Takahashi, Yoshinobu Kubota
  • Publication number: 20150261019
    Abstract: An optical modulator includes a substrate, an electrode, and an optical waveguide. The substrate includes a flat portion and a protruding portion protruded from the flat portion. The electrode is supported by the protruding portion. The optical waveguide is formed inside the protruding portion and waveguides light to be modulated with a voltage applied to the electrode. The protruding portion contains a part, present on the side of the electrode, of a light distribution region over which the light waveguided by the optical waveguide is distributed. A height of a tip of the protruding portion from the flat portion is smaller than a width of the light distribution region along a protruding direction of the protruding portion. A width of the tip of the protruding portion is smaller than a width of the light distribution region along a direction perpendicular to the protruding direction of the protruding portion.
    Type: Application
    Filed: February 24, 2015
    Publication date: September 17, 2015
    Applicant: Fujitsu Optical Components Limited
    Inventors: Yoshihiko YOSHIDA, Masaharu Doi, Yoshinobu Kubota, Masaki Sugiyama
  • Publication number: 20150053377
    Abstract: A heat exchanger includes a heat transfer tube; a plurality of fins each having ark-shaped contact surfaces configured to be brought into contact with an outer peripheral surface of the heat transfer tube, each of the fins being attached from the outside in a radial direction of the heat transfer tube; an adhesive that bonds the outer peripheral surface of the heat transfer tube and the contact surface of each of the fins; and a position regulation portion which is provided between the fins adjacent to each other in the tube axis direction and regulates a position in the tube axis direction of each of the fins.
    Type: Application
    Filed: August 20, 2014
    Publication date: February 26, 2015
    Applicant: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Nobuhide Hara, Koichi Tanimoto, Yoshihiko Yoshida, Yukihiro Sakaguchi, Masahiro Yoshioka, Fumikazu Ogata