Surface-deformation measurement using the wavefront reconstruction technique

This paper describes a new method for the measurement of minute deformations of arbitrary three-dimensional objects, such as might occur due to applied stress. The method is an application of the wavefront reconstruction technique, as developed by Leith and Upatnieks, to the interferometry of three-dimensional diffusely reflecting objects. The theory of wavefront reconstruction is sketched. A detailed theory for the interpretation of the interference phenomena observed in terms of the translations and rotations undergone by a point on the object is presented. Experimental results verifying the method and the theory are shown.