Patents by Inventor Tatsuhiko Inagaki

Tatsuhiko Inagaki 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).

  • Optical information system to detect reflection of pit depth by evanescent wave
    Patent number: 5602819
    Abstract: The information recording and reproducing apparatus includes: a recording medium including a plurality of concavo-convex pits; a light source for emitting laser light; a section for changing an optical characteristic value of the laser light, using interaction between the laser light and the recording medium; and a light detector for detecting the optical characteristic value of the laser light after the interaction occurs, and then outputting a signal in response to the detected optical characteristic value. The section for changing the optical characteristic value includes an evanescent wave generating section for generating an evanescent wave from the laser light. The evanescent wave generating section changes the optical characteristic value in accordance with how much the concavo-convex pits of the recording medium influences the evanescent wave. Multivalued data is reproduced on the basis of the signal from the light detector.
    Type: Grant
    Filed: July 18, 1995
    Date of Patent: February 11, 1997
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuhiko Inagaki, Hiroshi Kohso, Makoto Kuwamoto
  • Recording and reproducing medium and a recording and reproducing apparatus
    Patent number: 5582896
    Abstract: A recording and reproducing medium includes: at least one recording and reproducing layer; and a heating layer which receives light for writing data, converts a part of energy of the light into heat, and selectively heats a desired portion of the recording and reproducing layer, thereby changing optical characteristics of the desired portion, wherein the heating layer converts the part of energy of the light into the heat by a surface plasmon resonance phenomenon.
    Type: Grant
    Filed: October 21, 1993
    Date of Patent: December 10, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Makoto Kuwamoto, Hiroshi Kohso, Tatsuhiko Inagaki
  • Recording medium having concavo-convex pits with a maximum and a minimum pit depth depending on the wavelength of a laser light
    Patent number: 5577016
    Abstract: The information recording and reproducing apparatus includes: a recording medium including a plurality of concavo-convex pits; a light source for emitting laser light; a section for changing an optical characteristic value of the laser light, using interaction between the laser light and the recording medium; and a light detector for detecting the optical characteristic value of the laser light after the interaction occurs, and then outputting a signal in response to the detected optical characteristic value. The section for changing the optical characteristic value includes an evanescent wave generating section for generating an evanescent wave from the laser light. The evanescent wave generating section changes the optical characteristic value in accordance with how much the concavo-convex pits of the recording medium influences the evanescent wave. Multivalued data is reproduced on the basis of the signal from the light detector.
    Type: Grant
    Filed: July 18, 1995
    Date of Patent: November 19, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuhiko Inagaki, Hiroshi Kohso, Makoto Kuwamoto
  • Information recording and reproducing device and a method using the same
    Patent number: 5463609
    Abstract: The information recording and reproducing apparatus includes: a recording medium including a plurality of concavo-convex pits; a light source for emitting laser light; a section for changing an optical characteristic value of the laser light, using interaction between the laser light and the recording medium; and a light detector for detecting the optical characteristic value of the laser light after the interaction occurs, and then outputting a signal in response to the detected optical characteristic value. The section for changing the optical characteristic value includes an evanescent wave generating section for generating an evanescent wave from the laser light. The evanescent wave generating section changes the optical characteristic value in accordance with how much the concavo-convex pits of the recording medium influences the evanescent wave. Multivalued data is reproduced on the basis of the signal from the light detector.
    Type: Grant
    Filed: October 20, 1993
    Date of Patent: October 31, 1995
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tatsuhiko Inagaki, Hiroshi Kohso, Makoto Kuwamoto