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:
Oct. 29, 2002
Filed:
Dec. 29, 1999
Applicant:
Inventor:
Willem G. Ophey, Eindhoven, NL;
Assignee:
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/00 ;
U.S. Cl.
CPC ...
G11B 7/00 ;
Abstract
In an optical scanning device suited for scanning two types of record carriers having a different thickness of their transparent layers and wherein an astigmatic element is used in combination with a quadrant detector for generating a focus error signal (S ), this signal, which is generated when one type of record carrier is scanned, can considerably be improved by arranging an aspheric surface profile in only the central part of the beam coming from said one type of record carrier.
Ophey, Willem. (2002). Optical scanning device for two types of record carriers (U.S. Patent No. 6473386). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/6473386
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile