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:
Nov. 04, 2008
Filed:
Jun. 15, 2006
Applicants:
Christopher James Evans, Higganum, CT (US);
William P. Kuhn, Tuscon, AZ (US);
Inventors:
Christopher James Evans, Higganum, CT (US);
William P. Kuhn, Tuscon, AZ (US);
Assignee:
Zygo Corporation, Middlefield, CT (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B 11/02 (2006.01);
U.S. Cl.
CPC ...
Abstract
A Fizeau or other interferometer is used to provide high resolution, in-situ calibration of an external angle measurement system such as widely spaced high stability plane mirror interferometers (HSPMIs)). The calibrated measurement system then measures mechanical tilt during shearing. The tilt data is used to correct the sheared data, preferably before computation of the rotationally invariant (RI) terms. Alternatively, the data may be used to compute the spurious quadratic term and correct after integration.