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. 16, 2008
Filed:
Aug. 14, 2001
Christian Büchler, Villingen-Schwenningen, DE;
Friedhelm Zucker, Villingen-Schwenningen, DE;
Christian Büchler, Villingen-Schwenningen, DE;
Friedhelm Zucker, Villingen-Schwenningen, DE;
Thomson Licensing, Boulogne Billancourt, FR;
Abstract
In order to obtain a corrected or compensated focus error signal or track error signal, it is proposed to generate primary and secondary scanning beams incident on adjacent tracks of an optical recording medium and to detect the primary and secondary scanning beams reflected from the optical recording medium in order to derive from them primary-beam and secondary-beam focus error signals or primary-beam and secondary-beam track error signals, which are subsequently normalized in order to obtain the compensated focus error signal or track error signal from the normalized primary-beam and secondary-beam error signals by means of weighted combinations. As a result of the normalization, the corrected or compensated focus error signal or track error signal is generated independently of the reflection properties of the respectively scanned track.