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:
Nov. 22, 2005
Filed:
Sep. 10, 1999
Applicants:
Seiji Takeuchi, Utsunomiya, JP;
Ichiro Tanaka, Utsunomiya, JP;
Yasuyuki Tomita, Utsunomiya, JP;
Inventors:
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B005/18 ;
U.S. Cl.
CPC ...
Abstract
A diffractive optical element, which is used for an optical system of an exposure apparatus, includes a light-shielding member composed of a laminated layer of Cr oxide and Cr at a periphery of an effective area.