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. 31, 2007
Filed:
Oct. 29, 2004
Applicant:
Wouter Onno Pril, Eindhoven, NL;
Inventor:
Wouter Onno Pril, Eindhoven, NL;
Assignee:
ASML Netherlands B.V., Veldhoven, NL;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B 11/02 (2006.01);
U.S. Cl.
CPC ...
Abstract
A lithographic apparatus includes an interferometer configured to measure a position of a mirror of the lithographic apparatus. For measuring unflatness of the mirror the interferometer includes a modulator configured to modulate a position of an input beam of the interferometer, a synchronous detector configured to synchronously detect an interfered, modulated beam, and a calculator configured to calculate an unflatness of an area of the mirror from an effect of the modulation of the position of the input beam on an output signal of the synchronous detector. The modulator can include a rotatable, tilted, plan plate.