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. 16, 1994
Filed:
Oct. 27, 1992
Hiroyuki Takahashi, Saitama, JP;
Shinichi Nagahara, Saitama, JP;
Pioneer Electronic Corporation, Tokyo, JP;
Abstract
A reading system of an optical disc has a pregroove having a wobbled inside wall and pits for representing recorded data, and a pair of photodetector elements for detecting a spot of a laser beam reflected on the optical disc. The wobbled inside wall is modulated so as to represent absolute time. A differential amplifier is provided for deriving the difference between outputs of photodetector elements. A gain variable amplifier is provided for adjusting the level of one of the outputs to the level of the other output, so that the difference becomes zero.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile