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:
Apr. 18, 1995
Filed:
Aug. 17, 1993
John M Webster, Forest Hills, NY (US);
Jacqueline M Mew, Forest Hills, NY (US);
Holographics, Inc., Long Island City, NY (US);
Abstract
Methods and apparatus for automatically analyzing anti-nodal patterns formed in the outer skin of a semi-monocoque structure when it is excited to vibrate at a resonant frequency at which out-of-plane displacement is optimized. The described principles of analysis may be utilized to analyze a recorded image of the anti-nodal patterns obtained by holographic interferometry, or to directly examine the anti-nodal pattern by scanning a test area of the surface with a beam of coherent radiation, e.g., a laser beam, and utilizing the Doppler effect, measuring, recording and displaying a contour map showing out-of-plane displacement of the surface for analysis. In the holographic record case, comparison of the fringe density of the anti-nodes against the density of any fringes which may occur along normally fringe-free lines of underlying structure reveals the type and location of any structural faults. In the laser Doppler system, faults are identified by comparing the surface displacement of the anti-nodes with any displacements occurring along lines of the underlying structure.