Patents by Inventor Tsutomu Yamaguchi

Tsutomu Yamaguchi 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: 7411122
    Abstract: There is provided a keyboard device for a keyboard musical instrument, which is capable of enhancing the key touch feeling sensed when each key is depressed, and durability of stoppers. Keys each open downward, and have side walls and an abutment portion provided inside the side walls. The abutment portion has a lower end located at approximately the same height as lower ends of the side walls. The keys each perform downward pivotal motion when depressed. Stoppers are arranged under the keys in a manner associated therewith, respectively, for abutment of the side walls and the abutment portion of the associated key thereagainst, for stopping downward pivotal motion thereof. The stoppers have a shock-absorbing property.
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: August 12, 2008
    Assignee: Kabushiki Kaisha Kawai Gakki Seisakusho
    Inventor: Tsutomu Yamaguchi
  • Publication number: 20080179601
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: October 30, 2007
    Publication date: July 31, 2008
    Inventors: Tadao TODA, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Patent number: 7405096
    Abstract: Provided is a manufacturing method of a nitride semiconductor device having a nitride semiconductor substrate (e.g. GaN substrate) in which dislocation concentrated regions align in stripe formation, the dislocation concentrated regions extending from a front surface to a back surface of the substrate, the manufacturing method being for stacking each of a plurality of nitride semiconductor layers on the front surface of the substrate in a constant film thickness. Grooves are formed on the nitride semiconductor substrate in the immediate areas of dislocation concentrated regions. Each of the nitride semiconductor layers is formed as a crystal growth layer on the main surface of the nitride semiconductor substrate to which the grooves have been formed.
    Type: Grant
    Filed: March 16, 2005
    Date of Patent: July 29, 2008
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Takashi Kano, Tsutomu Yamaguchi, Hiroaki Izu, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20080127807
    Abstract: A stopper for a keyboard-based musical instrument is provided for accomplishing a good stopping feeling of a pivotable member, thereby making it possible to improve a touch feeling and restrain collision noise and other noise. A stopper 7 for a keyboard-based musical instrument with which a pivotable member 6 comes into contact while said pivotal member pivotally moves in association with a key touch, thereby restraining the pivotal movement of said pivotable member 6, comprises a mass 26, a first cushion 25 laminated on a front side of said mass 26, and a second cushion 27 laminated on a back side of said mass 26. Preferably, the mass 26 is made of a metal, and the first cushion 25 is harder than the second cushion 27.
    Type: Application
    Filed: May 24, 2005
    Publication date: June 5, 2008
    Applicant: Kabushiki Kaisha Kawai Gakki Seisakusho
    Inventor: Tsutomu Yamaguchi
  • Patent number: 7372077
    Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: May 13, 2008
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masayuki Hata, Tadao Toda, Shigeyuki Okamoto, Daijiro Inoue, Yasuyuki Bessho, Yasuhiko Nomura, Tsutomu Yamaguchi
  • Publication number: 20080081679
    Abstract: A waterproof structure for a casing has a first casing, a second casing to be put together with the first casing, and a waterproof member formed of an elastic material to prevent water from penetrating between the first casing and the second casing. The second casing has a recess. The waterproof member has a peripheral part which, when fitted into the recess, prevents penetration of water. The peripheral part is provided at the periphery of the waterproof member, which is laid out all around space between the first casing and the second casing. A projection engages with a dent. A restriction part of the first casing, provided at a position facing the peripheral part and protruding toward the second casing, prevents the peripheral part from coming out.
    Type: Application
    Filed: September 10, 2007
    Publication date: April 3, 2008
    Applicant: Casio Hitachi Mobile Communications Co., Ltd.
    Inventors: Yasuhiko Kawasaki, Takeru Baba, Toshiyuki Murakami, Shigeru Kato, Tsutomu Yamaguchi
  • Publication number: 20080073664
    Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.
    Type: Application
    Filed: October 30, 2007
    Publication date: March 27, 2008
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Masayuki Hata, Tadao Toda, Shigeyuki Okamoto, Daijiro Inoue, Yasuyuki Bessho, Yasuhiko Nomura, Tsutomu Yamaguchi
  • Publication number: 20080069162
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: October 30, 2007
    Publication date: March 20, 2008
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20080067541
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: October 30, 2007
    Publication date: March 20, 2008
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20070292979
    Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.
    Type: Application
    Filed: March 20, 2007
    Publication date: December 20, 2007
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Masayuki Hata, Tadao Toda, Shigeyuki Okamoto, Daijiro Inoue, Yasuyuki Bessho, Yasuhiko Nomura, Tsutomu Yamaguchi
  • Publication number: 20070264738
    Abstract: A monolithic semiconductor laser having plural semiconductor lasers having different emission wavelengths from each other, including: a semiconductor substrate; a first double hetero-structure formed within a first area on the semiconductor substrate and having first clad layers disposed above and below a first active layer; and a second double hetero-structure formed within a second area on the semiconductor substrate and having second clad layers disposed above and below a second active layer. The first and second active layers are made of different semiconductor materials from each other. The first clad layers above and below the first active layer are of approximately the same semiconductor materials and the second clad layers above and below the second active layer are of approximately the same semiconductor materials.
    Type: Application
    Filed: July 20, 2007
    Publication date: November 15, 2007
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Takehiro Nishida, Motoharu Miyashita, Tsutomu Yamaguchi
  • Publication number: 20070235750
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: June 4, 2007
    Publication date: October 11, 2007
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Patent number: 7279344
    Abstract: A nitride-based semiconductor element having excellent element characteristics is obtained by forming a nitride-based semiconductor layer having excellent crystallinity without performing a long etching process. This nitride-based semiconductor element and the method thereof includes forming a mask layer having a recess portion on a substantially flat upper surface of an underlayer to partially expose the upper surface of the underlayer. A nitride-based semiconductor layer is laterally grown on the exposed part of the underlayer and the mask layer while forming a void on the recess portion of the mask layer. Thus, the strain of the laterally grown nitride-based semiconductor layer is so relaxed that the crystallinity of the nitride-based semiconductor layer is improved.
    Type: Grant
    Filed: September 11, 2006
    Date of Patent: October 9, 2007
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Nobuhiko Hayashi, Tatsuya Kunisato, Hiroki Ohbo, Tsutomu Yamaguchi
  • Patent number: 7260132
    Abstract: A semiconductor laser apparatus includes multiple light emitting points, and a simple ridge stripe structure for each of the light emitting points. At least one of the light emitting points is disposed at a location that is 0% to 15% of the width of a substrate of the apparatus from the center, in the width direction, of the substrate.
    Type: Grant
    Filed: April 5, 2006
    Date of Patent: August 21, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takehiro Nishida, Tsutomu Yamaguchi, Motoharu Miyashita
  • Publication number: 20070137461
    Abstract: A key for keyboard-based musical instrument is provided for ensuring high hydrophilia and thereby ensuring higher playing performance. A key 1 for an electronic piano 2 comprises a key body 10 made of an ABS resin, and a thin plate-shaped key touch member 11 adhered on the top surface of the key body 10. The key touch member 11 comprises a base 11b made of an ABS resin, and a hydrophilic polymer 11a added in the base 11b in a dispersed manner. While a player is playing a keyboard-based musical instrument, sweat at the tip of his/her finger is absorbed by the hydrophilic polymer 11a.
    Type: Application
    Filed: February 17, 2005
    Publication date: June 21, 2007
    Applicant: Kabushiki Kaisha Kawai Gakki Seisakusho
    Inventor: Tsutomu Yamaguchi
  • Patent number: 7224307
    Abstract: Electronic equipment includes an operation mechanism having a plurality of key buttons for inputting operations into the device by the user and a base member connecting the plurality of key buttons, both formed of a luminescent material, and a panel placed above the operation mechanism that is formed from a member which can transmit light emitted by the operation mechanism. A plurality of holes are provided to enable operation of the plurality of key buttons and to enable the user to judge the positions and functions of the key buttons for operation even in darkness.
    Type: Grant
    Filed: December 25, 2001
    Date of Patent: May 29, 2007
    Assignee: Sony Corporation
    Inventors: Toshiyuki Hisatsune, Tsutomu Yamaguchi, Hirokazu Okabe, Yutaka Sato
  • Publication number: 20070077669
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: December 4, 2006
    Publication date: April 5, 2007
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20070001192
    Abstract: A nitride-based semiconductor element having excellent element characteristics is obtained by obtaining a nitride-based semiconductor layer having excellent crystallinity without performing a long-time etching process. This nitride-based semiconductor element comprises a mask layer, having a recess portion, formed on a substantially flat upper surface of an underlayer to partially expose the upper surface of the underlayer, a nitride-based semiconductor layer formed on the exposed part of the underlayer and the mask layer while forming a void on the recess portion of the mask layer, and a nitride-based semiconductor element layer, formed on the nitride-based semiconductor layer, having an element region.
    Type: Application
    Filed: September 11, 2006
    Publication date: January 4, 2007
    Applicant: SANYO ELECTRIC CO., LTD
    Inventors: Nobuhiko Hayashi, Tatsuya Kunisato, Hiroki Ohbo, Tsutomu Yamaguchi
  • Publication number: 20060227831
    Abstract: A semiconductor laser apparatus includes multiple light emitting points, and a simple ridge stripe structure for each of the light emitting points. At least one of the light emitting points is disposed at a location that is 0% to 15% of the width of a substrate of the apparatus from the center, in the width direction, of the substrate.
    Type: Application
    Filed: April 5, 2006
    Publication date: October 12, 2006
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takehiro Nishida, Tsutomu Yamaguchi, Motoharu Miyashita
  • Publication number: 20060222036
    Abstract: A semiconductor laser device capable of reducing the threshold current and improving luminous efficiency and a method of fabricating the same are obtained. This semiconductor laser device comprises a semiconductor substrate having a principal surface and a semiconductor element layer, formed on the principal surface of the semiconductor substrate, having a principal surface substantially inclined with respect to the principal surface of the semiconductor substrate and including an emission layer.
    Type: Application
    Filed: March 31, 2006
    Publication date: October 5, 2006
    Inventors: Tsutomu Yamaguchi, Masayuki Hata, Takashi Kano, Masayuki Shono, Hiroki Ohbo, Yasuhiko Nomura, Hiroaki Izu