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:
Oct. 04, 1988
Filed:
Jul. 29, 1986
Hitachi Video Eng. Corp., Tokyo, JP;
Hitachi Ltd., Tokyo, JP;
Abstract
An optical information reproducing apparatus wherein a light spot is projected on a rotary disc on which information is recorded, thereby to reproduce the information recorded on the disc, is provided with detection means to detect an amount of eccentricity of the disc by counting a number of tracks on the disc which the light spot at rest traverses when the disc is rotated by one revolution, and eccentricity correction signal generation means to generate a sinusoidal wave signal whose amplitude is determined by the detected amount of eccentricity and whose period is determined by a rotational period of the disc. The position of the light spot is controlled in accordance with the sinusoidal wave signal and a tracking control signal.