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. 18, 1982
Filed:
Mar. 07, 1980
Applicant:
Inventors:
Phillip R Peterson, Albuquerque, NM (US);
Athanasios Gavrielides, Albuquerque, NM (US);
John H Erkkila, Dayton, OH (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B / ;
U.S. Cl.
CPC ...
356354 ; 3501 / ; 356363 ;
Abstract
A method and apparatus for detecting small angular deviations of an input beam which utilizes a pair of diffraction gratings in series, both of which are operating in the Wood's anomaly region. As a result, the output intensity of the doubly diffracted input beam is at a maximum. Any deviation from the Wood's anomaly region by the input beam will substantially reduce the intensity of the output. This intensity variance is detected and utilized as an indication of a small angular deviation of the input beam.