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:
Feb. 08, 2000
Filed:
Aug. 11, 1997
Applicant:
Inventor:
Melvyn H Kreitzer, Cincinnati, OH (US);
Assignee:
U.S. Precision Lens Inc., Cincinnati, OH (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ; G02B / ; G02B / ;
U.S. Cl.
CPC ...
359649 ; 359713 ; 359714 ; 359757 ; 359764 ;
Abstract
A projection lens for use with LCD panels is provided. The lens has a first lens unit which has a positive power and a second lens unit which has a negative power. The first lens unit contains at least four lens elements, namely, a positive first lens element, a negative second lens element which is composed of a high dispersion material, a third lens element of weak optical power, and a positive fourth lens element of strong optical power. The projection lens achieves a correction of chromatic aberration on the order of about a quarter of pixel for large LCD panels having pixels on the order of 200 microns.