Patents by Inventor Yukio Kubata

Yukio Kubata 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 pickup apparatus and a hologram element used for same
    Patent number: 5331621
    Abstract: An optical pickup apparatus including a light emitting source, a hologram element for scanning a recording medium with light beams emitted from the light emitting source, a hologram lens for focusing the light beams introduced from the hologram element on the recording medium, an optical detector for detecting the light beams reflected from the recording medium, and a first optical system for directing the light beams reflected from the recording medium to the optical detector. The hologram element includes an optical diffraction grating for diffracting the light beams emitted from the light emitting source and a control means for controlling the rotation of the hologram element in a swinging manner. The hologram element can have hologram gratings on both surfaces thereof; one of them has a pattern of straight lines and the other has a pattern of concentric circles to obtain a widened deflection angle.
    Type: Grant
    Filed: December 2, 1992
    Date of Patent: July 19, 1994
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takahiro Miyake, Yoshio Yoshida, Katushiro Kubo, Tetsuo Ueyama, Yukio Kubata