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:
Jan. 07, 2020
Filed:
Jan. 18, 2019
Carl Zeiss Smt Gmbh, Oberkochen, DE;
Jochen Hetzler, Aalen, DE;
CARL ZEISS SMT GMBH, Oberkochen, DE;
Abstract
A measurement apparatus () for determining a shape of an optical surface. An illumination module () produces an illumination wave (), an interferometer () splits the wave into a test wave (), which is directed onto the optical surface, and a reference wave (). The relative tilt between the waves produces a multi-fringe interference pattern () in a detection plane () of the interferometer when the waves are superposed. A pupil plane () of the illumination module is arranged in a Fourier plane of the detection plane and the illumination module is configured to produce the illumination wave so that the intensity distribution thereof in the pupil plane includes at least one spatially isolated and contiguous surface region () such that a rectangle () with the smallest possible area fitted to the surface region or the totality of surface regions has an aspect ratio of at least 1.5:1.