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. 07, 2012
Filed:
May. 30, 2006
Mitsuru Sakai, Osaka, JP;
Yoshihiro Kanda, Osaka, JP;
Takashige Hiratsuka, Ehime, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A phase error detection apparatus capable of performing offset correction of a tracking error signal accurately even when there is a defect or a non-recorded position on an optical disc. There are provided a phase difference detection circuit () which receives two sequences of digital signals, performs phase comparison using a distance between zerocross points of the two sequences of digital signals, and outputs a phase comparison result PCR and a phase comparison completion signal PCC, and an offset control circuit () which outputs an offset correction amount for each phase comparison completion signal PCC from the phase difference detection circuit (), and the offset correction amount Δα is added to the phase comparison result PCR to avoid offset correction in a position where phase comparison is not carried out.