Patents by Inventor Yu Tokunaga

Yu Tokunaga 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: 9741913
    Abstract: Provided are a light-emitting diode which prevents degradation of reflectance and which enables high-luminosity light emission, and its manufacturing method. Such a light-emitting diode includes a substrate (1) upon which are provided, in this order, a reflecting layer (6), a transparent film (8) wherein multiple ohmic contact electrodes (7) are embedded at intervals, and a compound semiconductor layer (10) including a current diffusion layer (25) and a light-emitting layer (24) in this order. The periphery of the surface of each ohmic contact electrode (7) on the substrate (1) side are covered by the transparent film (8), and the ohmic contact electrodes (7) contact the reflecting layer (6) and the current diffusion layer (25).
    Type: Grant
    Filed: August 7, 2012
    Date of Patent: August 22, 2017
    Assignee: SHOWA DENKO K.K.
    Inventors: Yu Tokunaga, Atsushi Matsumura
  • Patent number: 9705043
    Abstract: In a light-emitting diode, a plurality of dot-shaped ohmic contact electrodes are provided between a metal reflective film and a compound semiconductor layer, an ohmic electrode and a surface electrode composed of a pad portion and a plurality of linear portions connected to the pad portion are provided in that order on the opposite side of the compound semiconductor layer from the semiconductor substrate, the surface of the ohmic electrode is covered with the linear portions, the ohmic contact electrodes and the ohmic electrode are formed in positions that do not overlap with the pad portion in plan view, and among the plurality of ohmic contact electrodes, 5% or more and 40% or less of the ohmic contact electrodes are disposed in positions that overlap with the linear portions in plan view.
    Type: Grant
    Filed: October 8, 2013
    Date of Patent: July 11, 2017
    Assignee: SHOWA DENKO K.K.
    Inventors: Atsushi Matsumura, Yu Tokunaga
  • Publication number: 20150255680
    Abstract: In a light-emitting diode, a plurality of dot-shaped ohmic contact electrodes are provided between a metal reflective film and a compound semiconductor layer, an ohmic electrode and a surface electrode composed of a pad portion and a plurality of linear portions connected to the pad portion are provided in that order on the opposite side of the compound semiconductor layer from the semiconductor substrate, the surface of the ohmic electrode is covered with the linear portions, the ohmic contact electrodes and the ohmic electrode are formed in positions that do not overlap with the pad portion in plane view, and among the plurality of ohmic contact electrodes, 5% or more and 40% or less of the ohmic contact electrodes are disposed in positions that overlap with the linear portions in plane view.
    Type: Application
    Filed: October 8, 2013
    Publication date: September 10, 2015
    Applicant: SHOWA DENKO K.K.
    Inventors: Atsushi Matsumura, Yu Tokunaga
  • Publication number: 20140183588
    Abstract: Provided are a light-emitting diode which prevents degradation of reflectance and which enables high-luminosity light emission, and its manufacturing method. Such a light-emitting diode includes a substrate (1) upon which are provided, in this order, a reflecting layer (6), a transparent film (8) wherein multiple ohmic contract electrodes (7) are embedded at intervals, and a compound semiconductor layer (10) including a current diffusion layer (25) and a light-emitting layer (24) in this order. The periphery of the surface of each ohmic contact electrode (7) on the substrate (1) side are covered by the transparent film (8), and the ohmic contact electrodes (7) contact the reflecting layer (6) and the current diffusion layer (25).
    Type: Application
    Filed: August 7, 2012
    Publication date: July 3, 2014
    Applicant: SHOWA DENKO K.K.
    Inventors: Yu Tokunaga, Atsushi Matsumura
  • Patent number: 5349295
    Abstract: For the purpose of three-dimensionally imaging a selected three-dimensional region of a subject under examination on the basis of magnetic resonance phenomena exhibited by hydrogen atomic nuclei, a magnetic resonance imaging apparatus comprises a unit for carrying out the contrast enhanced-fuirier acquiered steadystate technique (CE-FAST) extended to three dimensions, an image reconstruction unit for reconstructing a plurality of relatively thin slice images on the basis of echo signals from the three-dimensional region acquired by the unit, a weighting unit for weighting differently the plurality of relatively thin slice images obtained by the image reconstructing unit, an adding unit for adding slice images obtained by the weighting unit so as to produce a surface anatomy scan image of the three-dimensional region, and an image display unit for displaying the surface anatomy image obtained by the adding unit.
    Type: Grant
    Filed: September 23, 1992
    Date of Patent: September 20, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yu Tokunaga
  • Patent number: 5243283
    Abstract: A method of nuclear magnetic resonance angiographic imaging capable of reducing an imaging operation time.
    Type: Grant
    Filed: June 21, 1991
    Date of Patent: September 7, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yu Tokunaga, Hiroshi Sugimoto