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. 27, 1993
Filed:
Feb. 06, 1992
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
An optical disc system is provided with a focusing error signal generator for detecting any focusing error from light reflected by an optical disc and outputting a focusing error signal; a driver for outputting a focusing drive current on the basis of the focusing error signal; and an actuator for shifting an optical pickup in a focusing direction in accordance with the focusing drive signal. The optical disc system also has a signal detection and processing unit for detecting each index point (ID) on the optical disc and generating an index gate signal indicating an address between the index point and another index point next to the first-mentioned index point in the tracking direction; and an inter-ID holder for holding, based on the index gate signal, the focusing error signal at a signal level right before the first-mentioned index point.