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:
Jul. 09, 2002
Filed:
Aug. 10, 1999
Josephus A. H. M. Kahlman, Eindhoven, NL;
Willem M. J. Coene, Eindhoven, NL;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
An apparatus for reading an optical data carrier ( ) in accordance with the invention, comprises a transducer ( ) for optically reading an optically readable pattern recorded in substantially parallel data tracks of the data carrier ( ). The transducer ( ) generates a read signal (S (t)) which is an indication of the optically readable pattern. The apparatus further includes unit for realizing a relative movement of the transducer ( ) with respect to the data carrier ( ). The apparatus also has correction unit ( ) for reducing tangential tilt (I ) and error, signal generating unit ( ) for generating an error signal (S (t) for the correction unit. The apparatus characterized in that the error signal generating unit ( ) are adapted to derive the error signal (S (t)) from a temporal asymmetry of the response of the read signal (S (t)) to the optically readable pattern.