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:
Aug. 01, 2017
Filed:
May. 28, 2015
Zygo Corporation, Middlefield, CT (US);
Xavier Colonna de Lega, Middlefield, CT (US);
Jan Liesener, Middletown, CT (US);
Zygo Corporation, Middlefield, CT (US);
Abstract
Methods include: directing test light and reference light along different optical paths, where a test object is in a path of the test light; forming an image of the test object on a multi-element detector by directing test light from the test object to the detector; overlapping the reference light with the test light on the detector; detecting an intensity of the overlapped test and reference light with the detector, the intensity being detected at a frame rate; and modulating an optical path difference (OPD) between the test and reference light at the detector while detecting the light intensity. The OPD is modulated at a rate and amplitude sufficient to reduce a contrast of fringes in a spatial interference pattern formed by the light at the detector over a frame of the detector. Accordingly, fringe-free images may be acquired real-time.