Patents by Inventor Shigeo Yamashita

Shigeo Yamashita 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: 7309879
    Abstract: A semiconductor laser element capable of reducing the contact resistance and the thermal resistance and realizing a high reliability is provided. The semiconductor laser element includes: a semiconductor substrate, an active layer formed on the semiconductor substrate, a ridge having a clad layer formed on the active layer and a contact layer formed on the clad layer, an insulation film covering the side surfaces of the clad layer, and an electrode connected to the contact layer, wherein the insulation layer has an end portion in the ridge thickness direction located between the upper surface and the lower surface of the contact layer.
    Type: Grant
    Filed: February 9, 2006
    Date of Patent: December 18, 2007
    Assignee: Opnext Japan, Inc.
    Inventors: Haruki Fukai, Hidetaka Karita, Atsushi Nakamura, Shigeo Yamashita
  • Publication number: 20060131593
    Abstract: A semiconductor laser element capable of reducing the contact resistance and the thermal resistance and realizing a high reliability is provided. The semiconductor laser element includes: a semiconductor substrate, an active layer formed on the semiconductor substrate, a ridge having a clad layer formed on the active layer and a contact layer formed on the clad layer, an insulation film covering the side surfaces of the clad layer, and an electrode connected to the contact layer, wherein the insulation layer has an end portion in the ridge thickness direction located between the upper surface and the lower surface of the contact layer.
    Type: Application
    Filed: February 9, 2006
    Publication date: June 22, 2006
    Inventors: Haruki Fukai, Hidetaka Karita, Atsushi Nakamura, Shigeo Yamashita
  • Patent number: 7052189
    Abstract: The present invention provides an optical electronic device which includes a package casing made of plastic, a plurality of metal-made leads which extend between the inside and the outside of the package casing and form electrode terminals at external portions thereof, a lead base which is arranged in an inner bottom of the package and is integrally formed with at least one or the plurality of leads, a support substrate which is fixed onto the lead base and includes a conductive layer of a given pattern on an upper surface thereof, an optical element which is fixed onto the support substrate, an optical fiber which extends between the inside and the outside of the package casing and has an inner end thereof to face the optical element to perform transmission and reception of light between the optical fiber and the optical element, one or a plurality of electronic parts fixed to the leads in the inside of the package casing, and conductive wires which electrically connect electrodes of the optical element, ele
    Type: Grant
    Filed: November 15, 2002
    Date of Patent: May 30, 2006
    Assignee: Renesas Technology Corporation
    Inventors: Hiroshi Naka, Masaaki Tsuchiya, Shigeo Yamashita
  • Patent number: 7029936
    Abstract: A semiconductor laser element capable of reducing the contact resistance and the thermal resistance and realizing a high reliability is provided. The semiconductor laser element includes: a semiconductor substrate, an active layer formed on the semiconductor substrate, a ridge having a clad layer formed on the active layer and a contact layer formed on the clad layer, an insulation film covering the side surfaces of the clad layer, and an electrode connected to the contact layer, wherein the insulation layer has an end portion in the ridge thickness direction located between the upper surface and the lower surface of the contact layer.
    Type: Grant
    Filed: July 11, 2003
    Date of Patent: April 18, 2006
    Assignees: Hitachi, Ltd., Renesas Eastern Japan Semiconductor, Inc.
    Inventors: Haruki Fukai, Hidetaka Karita, Atsushi Nakamura, Shigeo Yamashita
  • Patent number: 6851846
    Abstract: Disclosed herewith is a microchip having a micromixer therein. The mixromixer employs a mixing or extracting structure having (1) a first flow pass provided at a first level of the microchip; (2) a second flow pass provided at a second level of the microchip, which is different from the first level; (3) a third flow pass having a plurality of sub flow passes separately layered at the first level and each having a first end and second end thereof, each sub flow pass being connected to one of the first and second flow passes at the first end thereof; and (4) a fourth flow pass, provided at the first level, connected to the second ends of the sub flow passes so that, at least connecting portions between the fourth flow pass and the sub flow passes of the third flow pass, an extending direction of the fourth flow pass is substantially identical to those of the sub flow passes.
    Type: Grant
    Filed: June 14, 2002
    Date of Patent: February 8, 2005
    Assignee: Minolta Co., Ltd.
    Inventors: Yasuhisa Fujii, Shigeo Yamashita, Yasuhiro Sando, Koji Yamamoto, Shunichi Hayamizu
  • Publication number: 20040240503
    Abstract: A semiconductor laser element capable of reducing the contact resistance and the thermal resistance and realizing a high reliability is provided. The semiconductor laser element includes: a semiconductor substrate, an active layer formed on the semiconductor substrate, a ridge having a clad layer formed on the active layer and a contact layer formed on the clad layer, an insulation film covering the side surfaces of the clad layer, and an electrode connected to the contact layer, wherein the insulation layer has an end portion in the ridge thickness direction located between the upper surface and the lower surface of the contact layer.
    Type: Application
    Filed: July 11, 2003
    Publication date: December 2, 2004
    Applicants: Hitachi, Ltd., Renesas Eastern Japan Semiconductor, Inc.
    Inventors: Haruki Fukai, Hidetaka Karita, Atsushi Nakamura, Shigeo Yamashita
  • Publication number: 20040011413
    Abstract: Disclosed herewith is a microchip having a micromixer therein. The mixromixer employs a mixing or extracting structure having (1) a first flow pass provided at a first level of the microchip; (2) a second flow pass provided at a second level of the microchip, which is different from the first level; (3) a third flow pass having a plurality of sub flow passes separately layered at the first level and each having a first end and second end thereof, each sub flow pass being connected to one of the first and second flow passes at the first end thereof; and (4) a fourth flow pass, provided at the first level, connected to the second ends of the sub flow passes so that, at least connecting portions between the fourth flow pass and the sub flow passes of the third flow pass, an extending direction of the fourth flow pass is substantially identical to those of the sub flow passes.
    Type: Application
    Filed: June 14, 2002
    Publication date: January 22, 2004
    Inventors: Yasuhisa Fujii, Shigeo Yamashita, Yasuhiro Sando, Koji Yamamoto, Shunichi Hayamizu
  • Publication number: 20030113076
    Abstract: The present invention provides an optical electronic device which includes a package casing made of plastic, a plurality of metal-made leads which extend between the inside and the outside of the package casing and form electrode terminals at external portions thereof, a lead base which is arranged in an inner bottom of the package and is integrally formed with at least one or the plurality of leads, a support substrate which is fixed onto the lead base and includes a conductive layer of a given pattern on an upper surface thereof, an optical element which is fixed onto the support substrate, an optical fiber which extends between the inside and the outside of the package casing and has an inner end thereof to face the optical element to perform transmission and reception of light between the optical fiber and the optical element, one or a plurality of electronic parts fixed to the leads in the inside of the package casing, and conductive wires which electrically connect electrodes of the optical element, ele
    Type: Application
    Filed: November 15, 2002
    Publication date: June 19, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Hiroshi Naka, Masaaki Tsuchiya, Shigeo Yamashita
  • Patent number: 5754015
    Abstract: A multiscan compatible horizontal deflection driving circuit prevents the flow of an excessive current through a transistor in a horizontal deflecting circuit when the frequency of a horizontal synchronization signal is switched. In the horizontal deflection driving circuit according to the invention, when a frequency of an H sync pulse of an input composite video signal decreases, a driving power source voltage is reduced earlier than a reduction of a frequency of a horizontal driving pulse, thereby preventing an excessive collector current from flowing in the transistor in the horizontal deflecting circuit.
    Type: Grant
    Filed: February 20, 1996
    Date of Patent: May 19, 1998
    Assignee: Pioneer Electronic Corporation
    Inventors: Shiro Nagaoka, Shigeo Yamashita
  • Patent number: 5449110
    Abstract: A method of preparing a substrate (1) having terminal electrodes (2, 3) which are provided on its both surfaces and a through hole (4), having a conductive film (5) formed on its inner peripheral surface, provided between the terminal electrodes (2, 3), mounting a lead terminal (9) having a pair of branch portions (9a, 9b) for elastically holding said terminal electrodes (2, 3) therebetween to the substrate (1), dipping the substrate (1) in molten solder from its lower surface (1b), drawing out the substrate (1) and solidifying the molten solder, thereby soldering the lead terminal (9) to the terminal electrodes (2, 3).
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: September 12, 1995
    Assignee: Murata Mfg. Co., Ltd.
    Inventors: Hirokazu Tsuji, Shigeo Yamashita, Yasuaki Ohno
  • Patent number: 5181003
    Abstract: An electromagnetic solenoid valve in which a projecting portion disposed on a coil bobbin is abutted against and engaged with a plate so that rotation of the coil bobbin is stopped. As a result of this simple construction, shortcircuiting between the terminal of the coil and the plate can be prevented.
    Type: Grant
    Filed: May 7, 1991
    Date of Patent: January 19, 1993
    Assignee: Mitsubishi Denki K.K.
    Inventor: Shigeo Yamashita
  • Patent number: 5043638
    Abstract: A dynamic focus adjusting voltage generating circuit for generating a dynamic focus adjusting voltage to be applied to a CRT for displaying images. The circuit includes a horizontal output circuit for supplying a sawtooth wave current to the horizontal deflection coil of the CRT, and a series circuit connected in parallel with the terminals of the horizontal output circuit and consisting of a capacitor and an inductance coil connected in series with each other. An electric potential developed at a node between the capacitance and the inductance coil is used as the dynamic focus adjusting voltage.
    Type: Grant
    Filed: November 15, 1989
    Date of Patent: August 27, 1991
    Assignee: Pioneer Electronic Corporation
    Inventor: Shigeo Yamashita
  • Patent number: 4780879
    Abstract: A semiconductor laser device having a stripe-shaped active region defined between a pair of end surfaces, at least one of the end surfaces having a curved cross-section in a plane parallel to the active region with a radius of curvature from 10 to 300 .mu.m, the stripe of the active region having such a width that a single transverse mode and a multi-longitudinal mode are allowed. The laser beam emitted from this laser can have little astigmatism and small spot size.
    Type: Grant
    Filed: February 19, 1987
    Date of Patent: October 25, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Chinone, Shigeo Yamashita, Shin'ichi Nakatsuka, Akemi Yamanaka, Yuichi Ono, Toshihiro Kawano, Kazuhisa Uomi, Takashi Kajimura, Toshiaki Tanaka, Kunio Aiki
  • Patent number: 4506366
    Abstract: A semiconductor laser device including at least a laminated region of first, second, third and fourth semiconductor layers on a predetermined semiconductor substrate, wherein the third semiconductor layer has a refractive index smaller than that of the second semiconductor layer; the first and fourth semiconductor layers have a refractive index smaller than that of the second and third semiconductor layers and have a conductivity type opposite that of the second and third semiconductor layers; the forbidden band gap of the first and third semiconductor layers is greater than that of the second semiconductor layer; and at least the second and third semiconductor layers are bent so that the laser light generated inside the second semiconductor layer in the proximity of the laser light-emitting facets generates optical coupling in the third semiconductor layer and is emitted from the crystal facets of the third semiconductor layer.
    Type: Grant
    Filed: June 29, 1982
    Date of Patent: March 19, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Chinone, Yasutoshi Kashiwada, Shigeo Yamashita, Kunio Aiki
  • Patent number: 4426702
    Abstract: This invention consists in improvements in a buried-heterostructure laser with buried optical guide, and facilitates the oscillation of the laser in the fundamental mode thereof and also enhances the available percentage of production of the laser. An active layer and an optical guide layer are sandwiched between two cladding layers, to form an optical confinement region. The width of the semiconductor material assembly varies in the direction of the stacked layers, and the narrowest part thereof is located on a side opposite to the optical guide layer with reference to the position of the active layer. The side surface of said semiconductor material assembly parallel to the traveling direction of laser radiation is buried by a burying layer.
    Type: Grant
    Filed: July 15, 1981
    Date of Patent: January 17, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Shigeo Yamashita, Hiroshi Matsuda, Uichiroo Kobayashi, Masayoshi Kobayashi, Hisao Nakashima
  • Patent number: 4361887
    Abstract: A semiconductor laser light emitting element comprises a semiconductor substrate, a laminate region of semiconductor layers having at least a first, a second and a third semiconductor layer formed over the substrate and having a p-n junction defined therein. The first and third semiconductor layers have smaller refractive indices and greater forbidden band gaps than the second semiconductor layer and are opposite in conductivity type to each other. Provided are on the substrate a field effect transistor section having first and second electrodes and a gate electrode disposed between the first and second electrodes, a means for serving as an optical resonator for emitting light in the lengthwise direction of the p-n junction.
    Type: Grant
    Filed: February 29, 1980
    Date of Patent: November 30, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Michiharu Nakamura, Motohisa Hirao, Shigeo Yamashita, Tadashi Fukuzawa, Junichi Umeda
  • Patent number: 4337443
    Abstract: A semiconductor laser element is disclosed which includes a film of an amorphous material deposited on at least an optical output facet of the laser element and contains silicon and hydrogen as the indispensable components. The thickness of the amorphous film is preferably selected in the vicinity of (.lambda./4).multidot.m where .lambda. represents wavelength of laser light in the amorphous film and m represents an odd integer. A film of a transparent insulation material can be deposited over the amorphous film thereby to constitute a composite film. With the disclosed structure of the semiconductor laser element, increasement in a threshold current of the laser element can be suppressed to a minimum, while a maximum optical output power can be increased.
    Type: Grant
    Filed: February 25, 1980
    Date of Patent: June 29, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Jun-ichi Umeda, Toshikazu Shimada, Michiharu Nakamura, Yoshifumi Katayama, Takashi Kajimura, Shigeo Yamashita
  • Patent number: 4288757
    Abstract: In certain applications, it is desirable to have a semiconductor laser device having shorter wave lengths of oscillation than are possible with conventional semiconductor lasers. To accomplish this, a semiconductor laser device is formed having a double-hetero structure, which comprises a semiconductor substrate composed of a GaAsP crystal, a first cladding layer formed on the substrate and composed of a GaAlAsP crystal of one conducting type, an active layer formed on the first cladding layer and composed of GaInAsP crystal, and a second cladding layer formed on the active layer and composed of a GaAlAsP crystal of the conducting type reverse to that of the first cladding layer. The cladding layers disposed on both sides of the active layer have a lower refractivity and a larger band gap than the active layer.
    Type: Grant
    Filed: July 10, 1979
    Date of Patent: September 8, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Kajimura, Motohisa Hirao, Michiharu Nakamura, Takao Kuroda, Shigeo Yamashita, Jun-Ichi Umeda
  • Patent number: 4257011
    Abstract: A semiconductor laser device has stabilized longitudinal and transverse modes without excess optical noise for a modulated signal generated by mode interaction. The fundamental construction of the semiconductor laser device comprises a structure wherein a first semiconductor layer is sandwiched between second and third semiconductor layers which have a greater band gap and lower index of refraction than the first semiconductor layer. That region of at least one of the second and third semiconductor layers which is remote from the first semiconductor layer corresponds substantially to a radiation region and serves as a light non-absorptive region in the shape of a stripe. A semiconductor layer has portions lying on both sides of the semiconductor layer remote from the first semiconductor layer and has an effective complex refractive-index for laser light discontinuous at both ends of the semiconductor layer remote from the first semiconductor layer.
    Type: Grant
    Filed: July 28, 1978
    Date of Patent: March 17, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Michiharu Nakamura, Shigeo Yamashita, Takao Kuroda, Jun-ichi Umeda