Patents by Inventor Tadashi Okuda

Tadashi Okuda 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: 4669823
    Abstract: An apparatus for electromagnetically driving an objective in conformance with movements of an optical disc in the vertical direction and deviations from track possibly produced in rotation of the disc, to thereby accomplish an automatic focussing of a write and/or read light beam on the disc. A driven unit including the objective lens system is supported by closely wound coil springs for suppressing unwanted resonance which will otherwise be produced in the driving operation. The apparatus is effective for controlling the focussed position of the light beam both in recording and reproducing modes. The spring coils are integrally mounted on a stationary mounting member by molding.
    Type: Grant
    Filed: October 31, 1984
    Date of Patent: June 2, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Akira Iguma, Tadashi Okuda