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:
Sep. 20, 1988
Filed:
Nov. 06, 1987
Wilhelmus A Gijzen, Eindhoven, NL;
Wilhelm J Kleuters, Eindhoven, NL;
Bob Hoekstra, Eindhoven, NL;
Gerard E Van Rosmalen, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
An electro-optical apparatus comprising an objective (7) scans an optical disc (3) having a transparent protective layer (5) by means of a radiation beam (10) which, through the transparent layer, is focussed on a reflecting recording surface (4). The objective moves along the optical axis (19) for focussing the radiation beam on the recording layer and moreover performs limited pivotal movements. The position of the optical axis of the objective is corrected for obliquity of the surface of the optical disc, correction means (22A, B) being provided to tilt the objective through a correction angle, so that the angle between the optical axis and the normal to the disc surface is reduced.