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. 31, 2006
Filed:
Dec. 05, 2002
Bernardus Hendrikus Wilhelmus Hendriks, Eindhoven, NL;
Jorrit Ernst DE Vries, Eindhoven, NL;
Teunis Willem Tukker, Eindhoven, NL;
Bernardus Hendrikus Wilhelmus Hendriks, Eindhoven, NL;
Jorrit Ernst De Vries, Eindhoven, NL;
Teunis Willem Tukker, Eindhoven, NL;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
An optical head () for scanning an optical record carrier () is provided with a compensator () for compensating the field curvature aberration of the objective system () caused by operation of the optical head at a different field angles. A surface of the compensator () comprises a phase structure in the form of annular areas (), the areas forming a non-periodic pattern of optical paths of different lengths. The optical paths change as a function of field angle and form a field angle-dependent wavefront deviation that compensates field curvature of the optical head.