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. 08, 2009
Filed:
Aug. 23, 2006
Tomowaki Takahashi, Tokyo, JP;
Tomowaki Takahashi, Tokyo, JP;
Nikon Corporation, Tokyo, JP;
Abstract
An 8-mirror reflecting type projection optical system. A first reflecting image forming optical system forms an intermediate image of a first surface and a second reflecting image forming optical system forms an image of that intermediate image on a second surface. The first reflecting image forming optical system has a first reflecting mirror M, a second reflecting mirror M, a third reflecting mirror M, and a fourth reflecting mirror MThe second reflecting image forming optical system has a fifth reflecting mirror M, a sixth reflecting mirror M, a seventh reflecting mirror M, and an eighth reflecting mirror MThe first reflecting mirror M, the fourth reflecting mirror Mthe fifth reflecting mirror M, and the eighth reflecting mirror Mhave concave reflecting surfaces, and the seventh reflecting mirror Mhas a convex reflecting surface. One of the second reflecting mirror Mand the third reflecting mirror Mhas a concave reflecting surface, and the other has a convex reflecting surface. The width dimension of an arcuate effective image forming region is relatively large.