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:
Mar. 18, 2008
Filed:
Dec. 03, 2001
Christian Büchler, Villingen-Schwenningen, DE;
Christian Büchler, Villingen-Schwenningen, DE;
Thomson Licensing, Boulogne-Billancourt, FR;
Abstract
In an apparatus for reading from and/or writing to an optical recording medium, it is desirable, in particular in the case of track jumps, to detect the direction of the track jump, i.e. the direction of movement of an objective lens of the apparatus relative to the optical recording medium in order to be able to carry out corresponding track regulation. For this purpose, and also for determining the number of tracks crossed by the scanning beams, it is proposed to determine the number of zero crossings and also the phase difference between at least two error signals derived from the reflected scanning beams.