Abstract

Optical techniques have long been useful for obtaining measurements of flow fields and in experimental solid mechanics. The applications have touched upon a large class of measurement problems. The scope of the present paper will limit to application of these techniques in experimental solid mechanics. A common feature of most of the optical interferometry based methods is that the information is presented in the form of interference fringes in the image of the object under investigation. The interference pattern or the optical phase map provides a visual description of the changes in the optical path length undergone between the initial undeformed and deformed conditions of the specimen surface. While the global visualization of deformation fields is always informative and has been used to advantage in the area of nondestructive testing, there has developed a considerable amount of sustained interest to obtain quantitative information on the measurement of wavefront distortion caused by loading the specimen.

© 1996 IEEE