Patents by Inventor Masahiro HITAKA

Masahiro HITAKA 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: 20210305786
    Abstract: A QCL includes a semiconductor substrate and an active layer provided on the semiconductor substrate. The active layer has a cascade structure in which a unit laminate including a light emission layer which generates light and an injection layer to which electrons are transported from the light emission layer is laminated in multiple stages. The light emission layer and the injection layer each have a quantum well structure in which quantum well layers and barrier layers are alternately laminated. A separation layer including a separation quantum well layer having a layer thickness smaller than an average layer thickness of the quantum well layers included in the light emission layer and smaller than an average layer thickness of the quantum well layers included in the injection layer is provided between the light emission layer and the injection layer in the unit laminate.
    Type: Application
    Filed: March 26, 2021
    Publication date: September 30, 2021
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Kazuue FUJITA, Masahiro HITAKA
  • Patent number: 11075315
    Abstract: An optical semiconductor element includes a semiconductor substrate, a first laminated structure provided on a front surface of the semiconductor substrate, and a second laminated structure provided on the front surface of the semiconductor substrate, the first laminated structure includes a first quantum cascade region, the second laminated structure includes a dummy region having the same layer structure as the first quantum cascade region, a second quantum cascade region provided on the front surface of the semiconductor substrate via the dummy region, and one of the first quantum cascade region and the second quantum cascade region is a quantum cascade laser, and the other of the first quantum cascade region and the second quantum cascade region is a quantum cascade detector.
    Type: Grant
    Filed: April 17, 2019
    Date of Patent: July 27, 2021
    Assignee: HAMAMATSU PHOTONICS K.K.
    Inventors: Masahiro Hitaka, Akio Ito, Tatsuo Dougakiuchi, Kazuue Fujita, Tadataka Edamura
  • Publication number: 20190326466
    Abstract: An optical semiconductor element includes a semiconductor substrate, a first laminated structure provided on a front surface of the semiconductor substrate, and a second laminated structure provided on the front surface of the semiconductor substrate, the first laminated structure includes a first quantum cascade region, the second laminated structure includes a dummy region having the same layer structure as the first quantum cascade region, a second quantum cascade region provided on the front surface of the semiconductor substrate via the dummy region, and one of the first quantum cascade region and the second quantum cascade region is a quantum cascade laser, and the other of the first quantum cascade region and the second quantum cascade region is a quantum cascade detector.
    Type: Application
    Filed: April 17, 2019
    Publication date: October 24, 2019
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Masahiro HITAKA, Akio ITO, Tatsuo DOUGAKIUCHI, Kazuue FUJITA, Tadataka EDAMURA
  • Patent number: 10404037
    Abstract: A semiconductor laser device of an embodiment comprises: a first electrode having an opening for passage of laser light and arranged on a main surface of a substrate; and a second electrode arranged on a back surface of the substrate. A stacked structural body including an active layer and a photonic crystal layer is arranged between the substrate and the first electrode, and a current confinement layer having an opening for passage of a current is arranged between the stacked structural body and the first electrode. A maximum width of the opening of the current confinement layer is smaller than a maximum width of the opening of the first electrode, and a whole region defined by the opening of the current confinement layer fits within a region defined by the opening of the first electrode as viewed from the first electrode side toward the second electrode side.
    Type: Grant
    Filed: July 5, 2018
    Date of Patent: September 3, 2019
    Assignee: HAMAMATSU PHOTONICS K.K.
    Inventors: Akira Higuchi, Yoshitaka Kurosaka, Tadataka Edamura, Masahiro Hitaka
  • Publication number: 20190013647
    Abstract: A semiconductor laser device of an embodiment comprises: a first electrode having an opening for passage of laser light and arranged on a main surface of a substrate; and a second electrode arranged on a back surface of the substrate. A stacked structural body including an active layer and a photonic crystal layer is arranged between the substrate and the first electrode, and a current confinement layer having an opening for passage of a current is arranged between the stacked structural body and the first electrode. A maximum width of the opening of the current confinement layer is smaller than a maximum width of the opening of the first electrode, and a whole region defined by the opening of the current confinement layer fits within a region defined by the opening of the first electrode as viewed from the first electrode side toward the second electrode side.
    Type: Application
    Filed: July 5, 2018
    Publication date: January 10, 2019
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Akira HIGUCHI, Yoshitaka KUROSAKA, Tadataka EDAMURA, Masahiro HITAKA
  • Patent number: 9859683
    Abstract: A DFB laser element includes an active layer 4 having a multiple quantum well structure including a plurality of well layers 4B having different thicknesses, a diffraction grating layer 6 that is optically coupled to the active layer 4, and a pair of cladding layers with the active layer 4 and the diffraction grating layer 6 interposed therebetween. An effective refractive index of the diffraction grating layer 6 is high, and a thickness of the well layer 4B increases as a distance from the diffraction grating layer 6 increases. In this structure, it is possible to reduce dependence on temperature when the DFB semiconductor laser element is miniaturized.
    Type: Grant
    Filed: January 4, 2017
    Date of Patent: January 2, 2018
    Assignee: HAMAMATSU PHOTONICS K.K.
    Inventors: Masahiro Hitaka, Yutaka Takagi, Takahiro Sugiyama
  • Publication number: 20170201069
    Abstract: A DFB laser element includes an active layer 4 having a multiple quantum well structure including a plurality of well layers 4B having different thicknesses, a diffraction grating layer 6 that is optically coupled to the active layer 4, and a pair of cladding layers with the active layer 4 and the diffraction grating layer 6 interposed therebetween. An effective refractive index of the diffraction grating layer 6 is high, and a thickness of the well layer 4B increases as a distance from the diffraction grating layer 6 increases. In this structure, it is possible to reduce dependence on temperature when the DFB semiconductor laser element is miniaturized.
    Type: Application
    Filed: January 4, 2017
    Publication date: July 13, 2017
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Masahiro HITAKA, Yutaka TAKAGI, Takahiro SUGIYAMA
  • Patent number: D892656
    Type: Grant
    Filed: March 20, 2019
    Date of Patent: August 11, 2020
    Assignee: HAMAMATSU PHOTONICS K.K.
    Inventors: Tatsuo Dougakiuchi, Akio Ito, Masahiro Hitaka, Tadataka Edamura
  • Patent number: D892657
    Type: Grant
    Filed: March 20, 2019
    Date of Patent: August 11, 2020
    Assignee: HAMAMATSU PHOTONICS K.K.
    Inventors: Tatsuo Dougakiuchi, Akio Ito, Masahiro Hitaka, Tadataka Edamura
  • Patent number: D899279
    Type: Grant
    Filed: March 20, 2019
    Date of Patent: October 20, 2020
    Assignee: HAMAMATSU PHOTONICS K.K.
    Inventors: Tatsuo Dougakiuchi, Akio Ito, Masahiro Hitaka, Tadataka Edamura
  • Patent number: D899284
    Type: Grant
    Filed: March 20, 2019
    Date of Patent: October 20, 2020
    Assignee: HAMAMATSU PHOTONICS K.K.
    Inventors: Tatsuo Dougakiuchi, Akio Ito, Masahiro Hitaka, Tadataka Edamura