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. 28, 2006
Filed:
Sep. 08, 2004
Ulrich Wegmann, Koenigsbronn, DE;
Uwe Schellhorn, Aalen, DE;
Ralph Klaesges, Aalen, DE;
Joachim Stuehler, Aalen, DE;
Ulrich Wegmann, Koenigsbronn, DE;
Uwe Schellhorn, Aalen, DE;
Ralph Klaesges, Aalen, DE;
Joachim Stuehler, Aalen, DE;
Carl Zeiss SMT AG, Oberkochen, DE;
Abstract
In the case of a method and a measuring system for measuring the distortion of an optical imaging system with the aid of moiré patterns, an object grating with an object pattern is arranged in the object plane of the imaging system, and an image grating with an image pattern is arranged in the image plane of the imaging system. Both the object pattern and the image pattern in each case have a multiplicity of cells with sub-gratings of different grating properties, it being possible, in particular, for the sub-gratings to have different directions of periodicity and different phase angles. The object pattern and the image pattern are coordinated with one another in such a way that, when the object pattern is projected onto the image pattern with the aid of the imaging system, images of the sub-gratings of the object pattern superimpose in each case with assigned sub-gratings of the image pattern, accompanied by the generation of moiré sub-patterns, which are likewise present in the form of cells situated next to one another. As a result, it is possible simultaneously to determine distortion components for a plurality of image directions aligned transverse to one another. It is preferred to use phase-shift methods in order to evaluate the moiré sub-pattern.