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:
Aug. 14, 2007
Filed:
Apr. 15, 2002
Kenji Fujiune, Moriguchi, JP;
Yuuichi Kuze, Settsu, JP;
Shin-ichi Yamada, Katano, JP;
Katsuya Watanabe, Nara, JP;
Kenji Fujiune, Moriguchi, JP;
Yuuichi Kuze, Settsu, JP;
Shin-ichi Yamada, Katano, JP;
Katsuya Watanabe, Nara, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
An optical disk apparatus having a high reliability by evading collision between a condensing lens and an optical disk regardless whether the focus control is in the operative state or in the inoperative state, thereby preventing damage to the condensing lens and the optical disk. When the focus control is in the inoperative state, by using a reflection light amount from the optical disk (), it is ascertained that the focus of the light beam is in the vicinity of the information surface and the condensing lens () is driven to be apart from the optical disk ().