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:
May. 05, 2015
Filed:
Nov. 08, 2012
Zygo Corporation, Middlefield, CT (US);
Peter de Groot, Middletown, CT (US);
Jan Liesener, Middletown, CT (US);
Zygo Corporation, Middlefield, CT (US);
Abstract
An encoder head includes one or more components arranged to: i) direct a first incident beam to the diffractive encoder scale at a first incident angle with respect to the encoder scale; ii) receive a first return beam from the encoder scale at a first return angle, the first return angle being different from the first incident angle; iii) redirect the first return beam to the encoder scale as a second incident beam at a second incident angle; and iv) receive a second return beam back from the encoder scale at a second return angle, the second return angle being different from the second incident angle, in which a difference between the first incident angle and second incident angle is less than a difference between the first incident angle and the first return angle and less than a difference between the second incident angle and the second return angle.