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:
Dec. 14, 2004
Filed:
Jun. 28, 2002
Yasuhiro Omura, Kumagaya, JP;
Naomasa Shiraishi, Saitama, JP;
Issey Tanaka, Yokohama, JP;
Soichi Owa, Kumagaya, JP;
Toshihiko Ozawa, Fukaya, JP;
Shunsuke Niisaka, Fujisawa, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A projection optical system, which forms a reduced image of a first surface onto a second surface, has excellent optical performance without substantially being affected by birefringence despite the use of optical material having intrinsic birefringence. This is done by suitably arranging certain crystal axes of radiation transmissive members that make up the projection optical system relative to the optical axis of the projection optical system, and by suitably arranging the certain crystal axes of the radiation transmissive members relative to the crystal axes of other radiation transmissive members in the projection optical system.