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:
May. 08, 1990
Filed:
Mar. 07, 1989
Applicant:
Inventors:
Willem G Opheij, Eindhoven, NL;
Josephus J Braat, Eindhoven, NL;
Assignee:
U.S. Philips Corporation, New York, NY (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
250216 ; 350443 ; 35016221 ;
Abstract
An optical scanning device having a mirror-objective arranged between a radiation source and an object to be scanned, which mirror objective is a radiation-transparent body having a radiation window and concentric reflector on each of two opposite surfaces of such body. By providing at least one of the windows with an aspherical shape, the mirror objective is well corrected for spherical aberrations without imposing stringent requirements on the accuracy of such aspherical shape.