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:
Jul. 14, 1992
Filed:
Feb. 26, 1991
Applicant:
Inventors:
Satoshi Kusano, Tokorozawa, JP;
Toshio Suzuki, Tokorozawa, JP;
Yuji Tawaragi, Tokorozawa, JP;
Noriko Obitsu, Tokorozawa, JP;
Assignee:
Pioneer Electronic Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 4428 ; 369 4432 ; 369 4441 ;
Abstract
An optical disk player using quadrant type photodetector as light receiving means. The phase difference output by the time difference detection method is issued as a tracking error, and a DC component of differential output by the push-pull method is issued as a tilt error, and zero cross of said differential output is detected. By using this detection output for the detection of zero-cross timing on off-track, stable operation of the tracking servo unit is ensured.