The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 22, 2003
Filed:
Apr. 15, 2002
Kazuhiko Ono, Yokohama, JP;
Eiji Ikeda, Yokohama, JP;
Hiroshi Minoda, Yokohama, JP;
Akio Fukushima, Yokohama, JP;
Hiroaki Shioyama, Yokohama, JP;
Shigeki Inoue, Fujisawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An optical disc apparatus for recording information and/or reproducing on an optical disc which has at least two recording layers including layer and layer reproducible from one side of the disc. The apparatus includes an optical pickup having a laser source, an objective lens, and an actuator. A controller is provided which obtains a present layer information of a sector recording layer from light reflected from the disc, confirms a target layer information of a target recording layer, judges whether the present layer information is the same as the target layer information, and outputs a first control signal to the actuator when it is judged that the present layer information is layer and the target layer information is layer and outputs a second control signal to a slider.