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. 13, 2001
Filed:
Aug. 16, 2000
Applicant:
Inventor:
Josephus J. M. Braat, Eindhoven, NL;
Assignee:
U.S. Philips Corporation, New York, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 9/14 ; G02B 2/730 ;
U.S. Cl.
CPC ...
G02B 9/14 ; G02B 2/730 ;
Abstract
In a lens system for focusing a divergent beam in a small spot and comprising a collimator lens and an objective lens, the collimator lens is composed of a positive plastics lens element and a negative glass lens element. This collimator corrects the temperature-dependent spherical aberration of the objective lens. This lens system is very suitable for a scanning device and an apparatus for reading/writing high-density optical discs.