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:
Mar. 09, 1993
Filed:
Feb. 28, 1990
Hideaki Osawa, Yokohama, JP;
Naobumi Seo, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
Disclosed is an optical disk apparatus applied to a data writing/reproducing operation of a sample-servo formatted optical disk having a clock pit and two wobbled pits in each of servo regions. A photodetector receives reflected light of a light beam from the optical disk to produce a reflected light signal. A clock detection unit detects a change in intensity of reflected light components from the clock pit in response to the reflected light signal to produce a binary clock pit detection signal. A tracking error detection unit detects a change in peak intensity of reflected light components from the wobbled pits in each servo region in response to the reflected light signal to produce a binary tracking error signal representing the detected intensity difference. A determination unit is connected to the clock detection unit and the tracking error detection unit. The determination unit compares a phase of a clock pit detection signal with that of a tracking error signal to determine a crossing direction of a beam spot with respect to some of the tracks on the optical disk in accordance with the comparison result of the phases.