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:
Feb. 12, 2002
Filed:
Mar. 22, 1999
Naoharu Yanagawa, Tokorozawa, JP;
Takahiro Togashi, Tokorozawa, JP;
Shinichi Nagahara, Tokorozawa, JP;
Pioneer Electronic Corporation, Tokyo-to, JP;
Abstract
A light beam is emitted by a light source, and an optical system separates the light beam into a main-portion and a sub-portion. The main-portion of the light beam is guided to an information storage medium. A monitor detector receives the sub-portion of the light beam and outputs a detection signal. A controller controls the output power of the light beam emitted by the light source based on the detection signal. Thus, the light beam of the sub-portion, which is not generally used as a light beam to be irradiated on a storage medium, can be efficiently used, and hence the output power of the light beam from the light source may be accurately controlled.