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. 11, 1993
Filed:
Aug. 02, 1991
Peter J DeGroot, Seattle, WA (US);
Hughes Aircraft Company, Los Angeles, CA (US);
Abstract
Method and apparatus for determining if a surface of an object, such as a ball bearing (12), has a radius of curvature within a predetermined tolerance. A test system (10) includes an interferometer having a reference beam (20a) and a measurement beam (20b). The measurement beam is disposed for illuminating a surface of the object while the object is in motion. A cylindrical lens (24) is provided for forming the measurement beam into a linear, stripe-like pattern that illuminates the surface. The measurement beam reflects from the surface of the object to a beamsplitter (20) that combines the reflected measurement beam with a reflected reference beam. The test system further includes an imager (30), optically coupled to an output of the interferometer, for recording a two dimensional interferogram that results from a change in an optical path length of the measurement beam relative to an optical path length of the reference beam. The test system further includes a processor (32), coupled to an output of the imager, for comparing the interferogram recorded by the imager to a reference interferogram previously recorded from a surface of an object known to have a radius of curvature within the predetermined tolerance.