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. 30, 1997
Filed:
Jun. 07, 1995
Nikon Corporation, Tokyo, JP;
Abstract
A projection-exposing apparatus has a mask which has a pattern formed with a pitch P.sub.R, an illuminating optical system for applying illuminating light from a light source to the mask, a projection optical system for projecting an image of the pattern onto a photosensitive substrate, and a deflecting grating member formed with a pitch P.sub.G disposed between the light source and the pattern of the mask for generating diffracted light. The pitch P.sub.G of the deflecting grating member is defined in the relation P.sub.G =2P.sub.R. The diffraction grating member is remote from the pattern on the mask by a distance .DELTA.t, where .DELTA.t .gtoreq.P.sub.G /2NA.sub.IL, NA.sub.IL being the numerical aperture of the illumination optical system.