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:
Jun. 15, 2004
Filed:
Dec. 18, 1998
Shinji Ohta, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A recording and/or reproducing apparatus for an optical disc in which the loop gain variation in tracking servo control can be suppressed to cause the illuminated laser light to follow correctly the recording track center. An optical disc recording/reproducing device detects a traversing signal generated when the laser light traverses a track at the time of tracking servo pull-in and sets the amplification degree of a GCA so that the push-pull signals will be at a predetermined level. The optical disc recording/reproducing device holds the amplitude of the wobbling signals on memory as an initial setting value. On starting the recording or reproduction, the optical disc recording/reproducing device monitors the amplitudes of the wobbling signals during the recording or reproduction to compare the amplitudes to the initial setting value. The optical disc recording/reproducing device sets the amplification degree in meeting with the ratio of increase or decrease of the wobbling signals to control the GCA and the gain of the push-pull signals.