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:
Mar. 04, 2003
Filed:
May. 11, 2001
Melvyn H. Kreitzer, Cincinnati, OH (US);
U.S. Precision Lens Incorporated, Cincinnati, OH (US);
Abstract
A projection television system ( ) is provided which has a CRT ( ) and a projection lens system ( ) for forming an image on a screen ( ). The projection lens system ( ) is characterized by a diffractive optical surface (DOS) which provides color correction for the lens system. The diffractive optical surface (DOS) can be formed as part of a diffractive optical element (DOE) or as part of an existing lens element of the lens system. The diffractive optical surface (DOS) is located between the object side (S ) of the lens' first lens unit (U ) and the image side (S ) of the lens' third lens unit (U ). The distance between the diffractive optical surface (DOS) and the lens' aperture stop (AS) is less than 0.1·f , where f is the focal length of the projection lens ( ).