Patents by Inventor Katutoshi Sumida

Katutoshi Sumida 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 head, disc recording/reproducing apparatus, and objective lens drive method
    Publication number: 20040213115
    Abstract: An optical head includes an integrated unit (9) having a light-receiving portion for converting reflected light from a disc-shape recording medium (13) into an electric signal and a light source, an objective lens (11), a tracking coil (18a) for driving the objective lens (11) in a radial direction of the disc-shape recording medium (13), a focusing coil (18b) for driving the objective lens (11) in a focus direction of the disc-shape recording medium (13), a signal generation portion (102) for generating a focus error signal and a tracking error signal from the electric signal converted at the light-receiving portion, and a control portion (101) for controlling the tracking coil (18a) and the focusing coil (18b) on the basis of the focus error signal and the tracking error signal.
    Type: Application
    Filed: May 24, 2004
    Publication date: October 28, 2004
    Inventors: Hideki Nakata, Hironori Tomita, Toru Tanaka, Koji Okamura, Katutoshi Sumida