Automated analysis of holo-interferograms for determination of surface displacement.
01 January 1987
A method using an image digitizing system with a minicomputer to automatically determine surface displacement by evaluating holo-interferometric fringe patterns is presented. The problem of determining the sign of the displacement vector as well as the need to produce a monotonic phase change across the surface under observation is solved by utilizing the method of carrier fringes. A set of programs has been written so that the camera/computer system can view the pattern of carrier plus deformation fringes, and with a knowledge of the carrier, draw a profile plot of the out-of-plane surface deformation. The procedure is exemplified with a study of a centrally loaded disk.