Patents by Inventor Yoichi Ohtaka

Yoichi Ohtaka 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 waveguide transmitting light wave energy in single mode
    Patent number: 3997241
    Abstract: An optical waveguide for optical communication transmitting light wave energy in a single mode composed of a core of a first transparent dielectric material and successive layers of a second and a third transparent dielectric material coaxially covering the core, the refractive index of the first dielectric material being higher than that of the third dielectric material and the refractive index of the second dielectric material being lower than that of the third dielectric material.
    Type: Grant
    Filed: October 3, 1975
    Date of Patent: December 14, 1976
    Assignee: Hitachi, Ltd.
    Inventors: Shigeo Nishida, Shojiro Kawakami, Yoichi Ohtaka, Seiichi Onoda
  • Optical waveguide transmitting light wave energy in single mode
    Patent number: RE32475
    Abstract: An optical waveguide for optical communication transmitting light wave energy in a single mode composed of a core of a first transparent dielectric material and successive layers of a second and a third transparent dieletric material coaxially covering the core, the refractive index of the first dielectric material being higher than that of the third dielectric material and the refractive index of the second dielectric material being lower than that of the third dielectric material.
    Type: Grant
    Filed: March 14, 1985
    Date of Patent: August 18, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Shigeo Nishida, Shojiro Kawakami, Yoichi Ohtaka, Seiichi Onoda