Universitaet Stuttgart

Carl Mahr Holding Gmbh

Universitãt Stuttgart

Goran Baer

Wolfgang Osten

Christof Pruss

An interferometer for areally measuring an optically smooth surface is presented, including means for illuminating a surface region with a plurality of discrete object waves from different directions and comprising means which, on a detector, superimpose object waves reflected at the surface onto a reference wave that is coherent with a plurality of object waves in order to form an interferogram. The interferometer is distinguished by virtue of it being configured to illuminate the surface with a plurality of object waves at the same time and produce the reference wave by way of a Fizeau beam splitter plate or a Fizeau objective, and by virtue of the interferometer including an interferometer stop that is arranged in the beam path upstream of the detector, and imaging optics, wherein the interferometer stop is situated within, or slightly outside of, the Fourier plane of the imaging optics and said interferometer stop filters the object waves reflected by the surface.

Interferometer using tilted object waves and comprising a Fizeau interferometer objective

The invention relates to a method for calibrating a measuring device, comprising the following steps: moving, with finite accuracy and thus with positioning error, to various points that lie in a testing volume of the measuring device and that can be characterized by spatial and/or angular coordinates, generating measurement signals at the respective points, and determining parameters of a computing model of the measuring device from the measurement signals and the spatial and/or angular coordinates. The method is characterized in that a coordinate system to which the coordinates of the points of the testing volume relate is defined from points moved to with error, by associating predetermined coordinate values with exactly six coordinates of three points.

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Berlin, Germany

Goran Baer