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:
Jan. 27, 2009
Filed:
Aug. 29, 2003
Shinichiro Iimura, Tokyo, JP;
Shinichiro Iimura, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
An optical reading unit which ensures that address information recorded as guide groove wobbles on an optical recording medium is easily played back. A light-receiving device () for detecting returning light from the optical recording medium has detection areas (A to D) delimited by a plurality of split lines (), (), and (). The position of one of the split lines functioning as a detection reference line is changed according to the position of a returning light spot S on a light-receiving surface () of the light-receiving device () and push-pull signals (PPto) are acquired by calculating the difference between signals received on two detection areas delimited by the split line to eliminate common-mode components.