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:
Dec. 30, 1997
Filed:
Apr. 19, 1996
Hidenobu Noda, Kanagawa, JP;
Sony Corporation, , JP;
Abstract
In a tracking servo circuit for such as an optical disc device, and the like, a tracking error signal TE obtained in a servo-off state is subjected to A/D conversion, the center level thereof is calculated at a center level computation circuit, that value is stored in a register, at a time of servo-on, switches are connected to one terminal side, in the normal operation mode, the center level stored in the register is subtracted from the tracking error signal TE obtained at the time of the servo-on state at the subtraction circuit, the offset of the tracking error signal is corrected, and when light reflected from the surface of the disc can no longer be obtained due to an accidental cause, the connection of another switch is switched to the terminal b in response to the switching of the signal FOK generated based on the RF signal to the low level, and the offset correction operation of the tracking error signal TE is stopped.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile