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. 30, 2010
Filed:
May. 23, 2007
Alexander Kremer, Stamford, CT (US);
Alexander Kremer, Stamford, CT (US);
ASML Holding N.V., Veldhoven, NL;
Abstract
Ellipticity in an illumination beam may be corrected by measuring an ellipticity of the illumination beam and substantially eliminating the ellipticity using a light attenuating filter at a defocus position of the illumination beam, wherein the light attenuating filter has a two-dimensional pattern that compensates for ellipticity variations in the illumination beam. The light attenuating filter may stand alone, or the filter may be combined with a uniformity correction system, such that it corrects both uniformity and ellipticity. In one embodiment, the light attenuating filter is printed with an assembly of microscopic dots according to the two-dimensional pattern.