Patents by Inventor Toru Ishikawa

Toru Ishikawa 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: 5236864
    Abstract: A method of manufacturing a surface-emitting-type semiconductor laser device having a buried structure. A GaAlAs film is used as a mask layer in forming a GaAlAs/GaAs system burying part around a GaAlAs/GaAs system buried part. The mask layer can be formed continuously together with an active layer, a cladding layer and the like which constitute the buried part by means of a crystal growing apparatus for forming the buried part. When the system is etched, the GaAlAs film mask prevents the system buried part from becoming undercut so that the mask has better resistance to peeling during subsequent processing.
    Type: Grant
    Filed: May 12, 1992
    Date of Patent: August 17, 1993
    Assignees: Research Development Corporation of Japan, Tokyo Institute of Technology, Sanyo Electric Co., Ltd.
    Inventors: Kenichi Iga, Akira Ibaraki, Kenji Kawashima, Kotaro Furusawa, Toru Ishikawa
  • Patent number: 5124752
    Abstract: A developing apparatus comprises a developing roll for carrying single-component toner to a developing area facing an electrostatic latent image carrier; a toner agitation chamber provided along an axis of the developing roll; a toner carry-in path projectingly provided on one end of the toner agitation chamber; and a toner carry and supply member for carrying the toner from the toner carry-in path into the toner agitation chamber along the axis of the developing roll and for supplying the toner from the toner agitation chamber onto the developing roll, the toner carry and supply member being established so that the quantity of toner carrying per unit time at the toner agitation chamber on the toner carry-in path side is larger than the quantity of toner carrying per unit time in the toner carry-in path.
    Type: Grant
    Filed: March 15, 1991
    Date of Patent: June 23, 1992
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Makoto Kanno, Yoshio Shinna, Akihiko Kato, Toru Isosu, Toru Ishikawa
  • Patent number: 5020066
    Abstract: A surface-emitting-type semiconductor laser device having a buried structure wherein a burying part having a current blocking function is formed around a buried part comprising an active region. A reflecting mirror consisting of a semiconductor multilayer film is installed on the buried part and the burying part, and the Bragg wavelength of this semiconductor multilayer film is set in matching with a longitudinal mode one mode higher than the longitudinal mode of oscillation in pulse operation. This semiconductor multilayer film has a configuration wherein two kinds of GaAlAs layers having different composition ratios of Al are laminated alternately, and the layer thickness of each GaAlAS layer constituting the semiconductor multilayer film is set so as to able to realize the Bragg wavelength calculated theoretically.
    Type: Grant
    Filed: December 27, 1989
    Date of Patent: May 28, 1991
    Assignees: Development Corporation of Japan, Tokyo Institute of Technology, Sanyo Electric Co., Ltd.
    Inventors: Kenichi Iga, Akira Ibaraki, Kenji Kawashima, Kotaro Furusawa, Toru Ishikawa