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:
May. 02, 1995
Filed:
Apr. 15, 1993
Friedrich Fuldner, Villingen-Schwennigen, DE;
Hans-Robert Kuhn, St. Georgen, DE;
Dieter Storz, Lauterbach, DE;
Deutsche Thomson-Brandt GmbH, Villengen-Schwennigen, DE;
Abstract
With an optical playback device, for example, with a compact disk player, care should be taken to see that the light beam scanning the data radiates as perpendicular as possible onto the disk. However, as a consequence of disk slap or chattering, the radial and the tangential angles alter during every revolution of the disk. As a result of the tolerances in the disk and the device, the optical axis deviates from the perpendicular in many cases. In order to regulate the radial angle .phi.R and the tangential angle .phi.T, under which the light beam strikes the disk, the data signal is demodulated in an amplitude demodulator. The regulating signal UR=C* sin .phi.* cos .alpha. for the radial angle .phi.R and the regulating signal UT=-C* cos .phi.* sin .alpha. for the tangential angle .phi.T are generated from the amplitude C and the phase position .phi. of the demodulated data signal.