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:
Dec. 06, 1999
Applicant:
Inventors:
Tsai-Sheng Gau, Hsinchu, TW;
Chin-Chiu Hsia, Taipei, TW;
Assignee:
Industrial Technology Research Institute, Hsin-Chu, TW;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03F 7/20 ;
U.S. Cl.
CPC ...
G03F 7/20 ;
Abstract
A design method, based on the principle of superposition, is presented for complex apertures used to form a filter for condenser lens illumination in an optical reduction system. The method is relatively simple to implement and achieves near optimum results without the need to perform long and error prone calculations. Both OPE and DOF are simultaneously optimized over a wide range of duty ratios.