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:
Nov. 20, 2007
Filed:
Jul. 29, 2004
Keishi Ueno, Saitama, JP;
Kiyoshi Shidara, Saitama, JP;
Keishi Ueno, Saitama, JP;
Kiyoshi Shidara, Saitama, JP;
TEAC Corporation, Musashino-shi, Tokyo, JP;
Abstract
An optical disc apparatus provided with an automatic power control circuit which controls power of laser light by obtaining a difference between a value detected by a front monitorand a target value individually for reproduction power and for recording power includes: a detectorfor detecting light reflected from an optical disc, a sample-hold circuitwhich performs on an output of the detectora sample-hold operation at the timing of the reproduction power; and a microcomputerwhich computes a reference value from the reflected light of the reproduction power at the timing just before the start of a recording operation after receiving a recording command until opening of a recording gate, and at the time of recording operation an intensity of reflected light on which a sample-hold operation is performed is compared with the reference value to correct a target value of the reproduction power.