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:
Aug. 24, 1982
Filed:
Jun. 04, 1980
Kazuo Hirasawa, Amagasaki, JP;
Takahiro Kubo, Amagasaki, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
An apparatus for tracking, by means of radiating beams of light, a record disc (6) which contains video or audio signals recorded in optical form. First and second lasers (1a, 1b) generate a first beam for reading out recorded information, and a second beam for tracking, respectively. The first beam provides a first optical spot (8a) on an information track (7) and the second beam provides a second optical spot (8b) in close proximity to the first spot. The first and second beams are selected alternately. The reflected second beam is detected by a radiation-sensitive detector (20) and compared with a reference signal level. The position of the optical system (200), including the first and second lasers, is physically adjusted by shifting means (14) in response to amplitude differences between the detected signal caused by the second beam and the reference signal level to implement accurate tracking control in spite of spindle hole eccentricities or the like.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile