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. 26, 2002
Filed:
Jul. 07, 2000
Kiyoto Mashima, Kawasaki, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A reflection reduction projection optical system having large numerical aperture for use in X-ray lithography. The reflection reduction projection optical system includes at least five aspheric surface reflecting mirrors and a reflecting mirror having a predetermined configuration, causing reduction imaging on an imaging surface I by imaging a light beam from an object O only one time. The reflection reduction projection optical system includes, in light path sequence from the object, a first convex mirror, a first concave mirror, the mirror having a predetermined configuration, a second concave mirror, a second convex mirror, and a third concave mirror. The reflection reduction projection optical system also includes an aperture stop located on the second convex mirror.