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. 14, 1992
Filed:
May. 23, 1990
Paul K Manhart, No. Hollywood, CA (US);
Abstract
A system for monitoring the configuration of a surface (e.g., a segmented parabolic surface) using orthogonally placed retroreflectors at sets of points A, B and C dispersed throughout the surface with a stationary halfwave plate HWP in the front of the one retroreflector at a corner point C and a rotating halfwave plate RHWP over a source of linearly polarized coherent light, thereby causing the direction of linear polarization to continuously rotate through 360.degree. and causing light returned by the retroreflector at point C to be continuously phase shifted through 360.degree. relative to light returned by retroreflectors at points A and B. The returned light from each set of points A. B and C is focused onto a bed-of-nails (BON) phase grating diagonally oriented with respect to the orthogonal orientation of the incident beams from retroreflectors A, B and C, thereby causing overlap in the light from points A and C and from points B and C to produce interferometric signals AC and BC. Any change in phase of the interferometric signals AC and BC indicates both the magnitude and direction of any change in the position of the retroreflector at point C relative to retroreflectors at points A and B.