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. 28, 2000
Filed:
Jul. 01, 1997
Xiaolu Chen, Saline, MI (US);
Cybernet Systems Corporation, Ann Arbor, MI (US);
Abstract
Material defects and damage are detected and evaluated by stressing the material and looking for flaw-induced anomalies in a fringe pattern generated by the interference between two coherent laser beams and electronic image processing. In terms of apparatus, the system includes a sensor head and a head-mounted display (HMD) interfaced to a computer, power supply, and control electronics. In one embodiment, the sensor head contains a thermal stressing unit and an in-plane displacement sensitive ESPI arrangement which measures the in-plane displacement of the deformation induced by applying thermal stressing. In operation, a thermal stressing unit is integrated with the sensor head to provide a slight temperature difference between a localized region and surrounding areas, with the change in temperature being used to reveal the defects and damage through the interference between the two laser beams and electronic image processing.