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:
Mar. 25, 1986
Filed:
May. 17, 1984
Hiroo Fujita, Tanashi, JP;
Citizen Watch Co., Ltd., Tokyo, JP;
Abstract
A surface shape measurement apparatus of non-contact type is based upon acousto-optical scanning means for producing a pair of polarized light beams differing in frequency by a fixed amount, which are scanned twice in succession across the surface to be measured in a succession of steps, with an electrical signal being produced by heterodyne interference of the resultant reflected light. Variations in phase of this signal, produced during the first scan, are processed to derive a set of data values representing measurement errors produced during the successive steps, which are utilized to correct a set of phase measurement values obtained during the second scan. The corrected phase measurement values thus obtained are integrated to produced surface shape data, with an accuracy of approximately 0.01 .mu.m or better being attainable.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile