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:
Jun. 06, 1995
Filed:
Aug. 25, 1993
Fujitsu Limited, Kawasaki, JP;
Abstract
An access control circuit for use in an optical disk unit including a linear drive mechanism for linearly sliding an optical head to thereby shift a beam spot to a target track on an optical disk. The slider of the linear drive mechanism and the optical head are integrally structured. The sliding speed of the linear drive mechanism is detected by a speed detection unit and the target speed of the linear drive mechanism is calculated by a target speed calculation unit. The difference between the sliding speed and the target speed is detected by a speed difference detection unit and thereby a speed difference signal is obtained. Then, the speed difference signal and a high-frequency signal from an oscillation unit are added together and the sum signal is output to a current supply unit, and thereby a drive current in accordance with the sum signal is supplied from the current supply unit to the linear drive mechanism to drive the same.