Patents by Inventor Shaw Ehara

Shaw Ehara 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: 5097298
    Abstract: A blue light emitting display element has a hetero p-n junction type light emitting layer formed between a semiconductor layer of a II-VI or III-V semiconducting compound having a wide energy bandgap and a highly electroconductive amorphous silicon type semiconductor layer which is of opposite conduction type and capable of forming a substantially ohmic contact with the semiconducting compound.
    Type: Grant
    Filed: November 30, 1990
    Date of Patent: March 17, 1992
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Shaw Ehara
  • Patent number: 4943503
    Abstract: An amorphous silicon (a-Si) photoreceptor includes an amorphous silicon (a-Si) photoconductive layer, and a surface layer disposed above the amorphous silicon (a-Si) photoconductive layer. An intermediate layer is disposed between the amorphous-silicon (a-Si) photoconductive layer and the surface layer to ensure the energy level matching. The intermediate layer is made of amorphous silicon (a-Si) doped with nitrogen and boron so as to have the energy difference of less than 0.2 eV between the bottom of the conduction bands of the surface layer and the intermediate layer.
    Type: Grant
    Filed: October 10, 1984
    Date of Patent: July 24, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hideo Nojima, Yoshimi Kojima, Eiji Imada, Toshiro Matsuyama, Takashi Hayakawa, Shiro Narikawa, Shaw Ehara
  • Patent number: 4907051
    Abstract: A photocathode with high photoelectric conversion ratio over an extended wavelength range of incident light has a hetero junction formed between thin films of a p-type amorphous silicon alloy having energy gap matching the energy of the incident light and an n-type semiconductor with small work function or large coefficient of secondary electron emission.
    Type: Grant
    Filed: May 12, 1988
    Date of Patent: March 6, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Shaw Ehara
  • Patent number: 4853309
    Abstract: A photoreceptor for electrophotography including an electrically conductive substrate, a bottom layer, a photoconductive layer composed mainly of amorphous silicon, and a surface layer, in that order. Both the bottom and surface layers have a greater optical bandgap than said photoconductive layer. A first middle layer is disposed between said bottom layer and said photoconductive layer, and a second middle layer is disposed between said photoconductive layer and said surface layer. Both the first and second middle layers are composed mainly of amorphous silicon and have a concentration of doped atoms which varies from the bottom to the top of the layer.
    Type: Grant
    Filed: June 3, 1988
    Date of Patent: August 1, 1989
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takashi Hayakawa, Hideo Nojima, Yoshimi Kojima, Shiro Narikawa, Toshiro Matsuyama, Eiji Imada, Shaw Ehara
  • Patent number: 4851256
    Abstract: An apparatus for manufacturing photosensitive amorphous silicon objects comprises a pair of coaxial cylindrical electrodes inside a reaction tank of a plasma CVD device. A plurality of cylindrical substrates of an electrically conductive material disposed between these electrodes. A source gas is injected into the reaction tank through a plurality of inlets evenly spaced on the outer peripheral wall so that films of uniform quality can be produced efficiently.
    Type: Grant
    Filed: December 9, 1987
    Date of Patent: July 25, 1989
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshiro Matsuyama, Yoshimi Kojima, Shaw Ehara
  • Patent number: 4687724
    Abstract: A photoreceptor for electrophotography utilizing a-Si:N:H:F, wherein a stable high-sensitive layer is provided and the time-lapse variation in characteristics is reduced in the use of an a-Si.sub.1-x N.sub.x layer as a sensitive layer.
    Type: Grant
    Filed: December 14, 1983
    Date of Patent: August 18, 1987
    Assignee: Sharp Kabushiki
    Inventors: Shaw Ehara, Yoshimi Kojima, Eiji Imada, Takashi Hayakawa, Toshiro Matsuyama
  • Patent number: 4666816
    Abstract: A method of manufacturing an electrophotographic photoreceptor having an amorphous silicon layer formed as a photoconductive layer, on an electrically conductive support member. The manufacturing method includes the steps of preparing the amorphous silicon layer as the photoconductive layer by employing Si.sub.2 H.sub.6 (disilane) as a main raw material gas through a glow discharge process, and simultaneously, adding nitrogen and boron to the main raw material gas, with the unsaturated bond being stabilized by hydrogen or hydrogen and fluorine.
    Type: Grant
    Filed: August 26, 1986
    Date of Patent: May 19, 1987
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshimi Kojima, Shiro Narikawa, Takashi Hayakawa, Hideo Nojima, Eiji Imada, Toshiro Matsuyama, Shaw Ehara
  • Patent number: 4615299
    Abstract: A plasma CVD (chemical vapor deposition) apparatus of the capacitance coupling type for effecting the chemical vapor deposition on a drum which includes an air tight chamber made of an electrically conductive material, a support provided in the chamber for supporting the drum inside the chamber in an electrically insulated relationship with the chamber, and an RF power source for supplying RF power to the drum. The chamber is grounded and, therefore, the plasma is generated between the drum and inside wall of the chamber. The apparatus is provided with means for providing a smooth surface on the drum. The drum can be used as a photoreceptor for use in an electrophotographic copying machine.
    Type: Grant
    Filed: March 7, 1985
    Date of Patent: October 7, 1986
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshiro Matsuyama, Takashi Hayakawa, Yoshimi Kojima, Shiro Narikawa, Shaw Ehara