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. 21, 2009
Filed:
May. 20, 2004
Takashi Miyamoto, Saitama, JP;
Tomohisa Inaba, Saitama, JP;
Kiyoshi Shidara, Saitama, JP;
TEAC Corporation, Tama-shi, Tokyo, JP;
Abstract
In an optical disc device, the recording laser light power from a semiconductor laser is adjusted to a desired power. A front monitor PD is provided near the semiconductor laser LD of an optical pickup, and the recording layer light power is detected. A system controllerstores in memory an approximating equation for a correction coefficient for the recording power based on the detection signal characteristic when the recording laser light is a multi-pulse signal, uses the approximating equation to compute the correction coefficient for the desired recording power, corrects the detected signal level from the front monitor PD, and executes feedback control of the laser power emitted from the LD.