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:
Jul. 20, 1993
Filed:
Jul. 08, 1991
Edwin S Gaynor, Gaithersburg, MD (US);
Industrial Quality, Inc., Gaithersburg, MD (US);
Abstract
A dual-interferometer apparatus for simultaneously measuring in-plane and out-of-plane ultrasonic displacements of the surface of materials comprising a single laser source, optical fibers, optical couplers and dividers, a phase-conjugate mirror, and a path length stabilizing system including a piezoelectric compensator. The present invention is unique in providing for the automatic alignment of the beams of the two interferometers, thus eliminating the need for time-consuming alignment procedures. The automatic alignment of the interferometers is achieved because a phase conjugate mirror is used to generate a counterpropagating beam used by both interferometers, and because the beams for the out-of-plane interferometer are derived from the beams used for the in-plane interferometer.