Patents by Inventor Eisaku Kato

Eisaku Kato 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: 6031244
    Abstract: A luminescent semiconductor device comprises: an active layer composed of a Group II-VI semiconductor device which comprises at least one Group II element selected from the group consisting of zinc, magnesium, beryllium, cadmium, manganese and mercury, and at least one Group VI element selected from the group consisting of oxygen, sulfur, selenium and tellurium. the Group II-VI compound semiconductor forming said active layer contains at least one element selected from the group consisting of magnesium, beryllium and cadmium as the Group II element and tellurium as the Group VI element. At least one antidiffusion layer preventing diffusion of these elements from the active layer is provided on at least one surface of the active layer.
    Type: Grant
    Filed: December 8, 1997
    Date of Patent: February 29, 2000
    Assignee: Sony Corporation
    Inventors: Hiroyasu Noguchi, Kazushi Nakano, Akira Ishibashi, Atsushi Toda, Satoshi Taniguchi, Tomonori Hino, Eisaku Kato
  • Patent number: 6020601
    Abstract: A semiconductor light-emitting device longer in life time and higher in reliability is provided which is formed of, on a substrate (1), a first conductivity type cladding layer (3) and a second conductivity type cladding layer (7) made of Zn.sub.x Mg.sub.Y Be.sub.1-x-y S.sub.Z Se.sub.1-z (0<x<1,0<y<1,0.ltoreq.z<1) system compound semiconductor, at least one active layer (5) made of Zn.sub.A Cd.sub.B Be.sub.1-A-B S.sub.c Se.sub.1-C (0<A.ltoreq.1, 0.ltoreq.B<1, 0.ltoreq.C<1), having a compressive distortion relative to the above substrate and located between the first and second conductivity type cladding layers, and at least one strain compensation layer having a tensile distortion relative to the above substrate and made of Zn.sub.u Cd.sub.1-u S.sub.v Se.sub.1-v (0<u.ltoreq.1, 0.ltoreq.v<1).
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: February 1, 2000
    Assignee: Sony Corporation
    Inventors: Hiroyasu Noguchi, Eisaku Kato, Masaharu Nagai
  • Patent number: 5740193
    Abstract: A II-VI group compound semiconductor light-emitting device can emit light of a short wavelength at room temperature. Operation characteristics, such as current--voltage characteristics and current--light output characteristics can be stabilized and a life of this semiconductor light-emitting device can be extended. The semiconductor light-emitting device comprises a substrate (1), at least a first cladding layer (2) of a first conductivity type, an active layer (3) and a second cladding layer (4) of a second conductivity type, wherein at least the active layer (3) is made of a II-VI group compound semiconductor and the active layer (3) is doped by either or both of n-type and p-type dopants.
    Type: Grant
    Filed: April 2, 1997
    Date of Patent: April 14, 1998
    Assignee: Sony Corporation
    Inventors: Hiroyuki Okuyama, Akira Ishibashi, Eisaku Kato, Hiroshi Yoshida, Kazushi Nakano, Masakazu Ukita, Satoru Kijima, Sakurako Okamoto
  • Patent number: 5657336
    Abstract: A II-VI group compound semiconductor light-emitting device can emit light of a short wavelength at room temperature. Operation characteristics, such as current--voltage characteristics and current--light output characteristics can be stabilized and a life of this semiconductor light-emitting device can be extended. The semiconductor light-emitting device comprises a substrate (1), at least a first cladding layer (2) of a first conductivity type, an active layer (3) and a second cladding layer (4) of a second conductivity type, wherein at least the active layer (3) is made of a II-VI group compound semiconductor and the active layer (3) is doped by either or both of n-type and p-type dopants.
    Type: Grant
    Filed: July 28, 1995
    Date of Patent: August 12, 1997
    Assignee: Sony Corporation
    Inventors: Hiroyuki Okuyama, Akira Ishibashi, Eisaku Kato, Hiroshi Yoshida, Kazushi Nakano, Masakazu Ukita, Satoru Kijima, Sakurako Okamoto
  • Patent number: 4130997
    Abstract: A refrigerator comprises a refrigerating cycle in which a refrigerant is charged and which includes a cooler for a freezing compartment, a closed loop which is branched from the refrigerating cycle and includes a cooler for a refrigerating compartment, and a heating device provided in the closed loop which supplies the refrigerant to the closed loop by means of vapor bubble pumping action, to thereby control the refrigerant flow in the closed loop.
    Type: Grant
    Filed: December 8, 1976
    Date of Patent: December 26, 1978
    Assignee: Hitachi, Ltd.
    Inventors: Toshitsugu Hara, Yoritsune Abe, Katsuji Ootuka, Yasushige Kashiwabara, Hiroichi Oshiyama, Michio Yanadori, Eisaku Kato, Kichizaemon Okazaki