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:
Jun. 28, 2011
Filed:
Jul. 09, 2007
Katsuya Watanabe, Nara, JP;
Akira Yoshikawa, Nara, JP;
Eiji Ueda, Osaka, JP;
Hiroshige Ishibashi, Osaka, JP;
Yuuichi Kuze, Osaka, JP;
Katsuya Watanabe, Nara, JP;
Akira Yoshikawa, Nara, JP;
Eiji Ueda, Osaka, JP;
Hiroshige Ishibashi, Osaka, JP;
Yuuichi Kuze, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
An optical disc apparatus includes: a defect detecting sectionfor detecting, based on a light detection signal and with respect to a preset detection reference level, a fingerprint or a bubble on the discas a defect to output a defect detection signal; and a waveform shaping sectionto output a hold signal that holds, in response to the defect detection signal, a signal from a tracking control sectionat a level just before the defect has occurred. The apparatus is initially operated not to hold the signal from the tracking control sectioneven if there is a defect. But once a tracking failure has occurred during a read operation, settings are changed to hold the signal from the tracking control sectionagainst the defect while the read operation is retried.