Patents by Inventor Koujiro Okamoto

Koujiro Okamoto 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: 6430119
    Abstract: An optical disk apparatus includes a converging section for converging a light beam toward an information carrier; a moving section for moving the light beam converged by the converging section in a direction perpendicular to a surface of the information carrier; a light detector for detecting the light beam reflected by the information carrier; a convergence state detecting section for generating a convergence state signal representing a convergence state of the light beam at a convergence point on the information carrier and outputting a reproduction signal from the information carrier, based on the output from the light detector; a focus controller for driving the moving section to make the convergence state constant based on the convergence state signal and a prescribed target position; a reproduction quality signal detector for detecting a reproduction quality signal representing a quality of the reproduction signal based on the reproduction signal; a reproduction quality signal measuring section for cha
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: August 6, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yuu Okada, Katsuya Watanabe, Tetsuya Shihara, Akihiko Nishioka, Koujiro Okamoto