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As the use of electronic devices in automobiles increases, the reliability of such devices is becoming increasingly important. One possible failure is due to leakage resulted from imperfect hermetical seal in mircochips and microelectronic packages. This paper presents an optical technique referred to as shearography for rapid evaluation of hermetics seals. The proposed process of leaking testing is very fast and practical.

This paper presents an optical method for evaluating residual stresses. The approach is based on measuring the deformation due to the relief of stress produced by a blind-hole drilling technique. The deformation is rapidly measured by shearography. Unlike the strain gage method, this method does not require mounting strain gages /transducers. A rapid process for detection of residual stress using a micro-indentation technique is also present. The method is practical for employment in a production/field environment.

A novel computer vision technique for rapid measurement of surface coordinates is presented. The technique is based on the marriage of a digital fringe projection technique and a fringe-phase extraction algorithm. A digitally controlled video signal in the form of linear and parallel fringes of cosinusoidal intensity variation is projected onto an object. The fringe pattern is perturbed by the three-dimensional object surface with fringe-phase containing information on the depth of the object. A phase extraction algorithm is used to determine the fringe-phase distribution, from which the three-dimensional surface coordinates are determined. The theoretical basis of this technique and some experimental results are presented in this paper.