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:
Nov. 20, 1990
Filed:
Mar. 02, 1989
Gerard E Van Rosmalen, Eindhoven, NL;
Wilhelm J Kleuters, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
Disclosed is a system for optically recording information on a disc-shaped record carrier body along an information track, with the write spot being accurately guided in the radial and tangential directions. The record carrier body comprises a servo track formed by a constant and large number of servo areas per revolution of the servo track. In addition to a write spot, the write apparatus also projects a servo spot on the servo track. The tangential speed and the radial position of the servo spot relative to the servo track are determined from the modulated servo beam and used to correct the tangential speed and the radial position of the write spot, which is locked to the servo spot.