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:
Sep. 22, 2009
Filed:
Nov. 29, 2006
Hiroshi Nomura, Kawasaki, JP;
Hiroshi Nomura, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A polarization evaluation mask for evaluating the state of polarization of an illumination light in exposure equipment comprises a transparent substrate; a light interceptor formed in said transparent substrate and having a plurality of fine apertures; a plurality of polarizers formed to cover said plurality of fine apertures and having orientation angles of the transmissive polarization differing in increments of certain angle; and a plurality of quarter-wave plates arranged upstream of said illumination light than said polarizers and formed as superimposed on said polarizers to cover said fine apertures, and having orientation angles of the fast axis differing in increments of certain angle. Each of said plurality of fine apertures has a different combination of said orientation angle of said polarizer and said orientation angle of said quarter-wave plate.