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:
Dec. 13, 2011
Filed:
Oct. 28, 2010
Masatoshi Yajima, Kadoma, JP;
Kenji Kawano, Kadoma, JP;
Masatoshi Yajima, Kadoma, JP;
Kenji Kawano, Kadoma, JP;
Panasonic Corporation, Osaka, JP;
Abstract
An optical drive includes: an optical pickup; a preprocessing circuit which processes an optical signal detected by the optical pickup; nonvolatile memory having stored therein relation information which represents the relation of a signal balance with respect to a signal difference between a TE signal and an FE signal at the time of a predetermined operation of the optical pickup; and a central processing circuit which performs focus control of the optical pickup. The preprocessing circuit generates the signal balance of the optical pickup. The preprocessing circuit also obtains the FE signal and the TE signal with respect to the optical disc. The central processing circuit derives a phase difference and an amplitude difference from the signal balance and the relation information, and calculates, based on the differences and the TE signal, a FE signal suitable for the predetermined operation.