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:
Jul. 18, 1995
Filed:
Apr. 19, 1994
Applicant:
Inventor:
Hiroyoshi Tanabe, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
355 53 ; 355 71 ; 430-5 ;
Abstract
A projector for exposing a photosensitive substrate includes a mask having an exposure pattern thereon composed of half-transparent material which causes a phase difference among lights passing therethrough, a first optical system for illuminating the mask, a second optical system for projecting the exposure pattern on the photosensitive substrate, and a device, disposed ahead of the first optical system, for controlling a quantity of illumination light to be irradiated in a plurality of areas of the first optical system.