Holographic interferometry applied to measurements of small static displacements of diffusely reflecting surfaces

A general relation is derived by which small displacements of a diffusely reflecting surface may be determined using holographic interferometry. It is shown how a single hologram method of analysis, utilizing parallax and fringe counting, and a multiple hologram method, using interference order assignment are related. Both methods may be viewed in a unified manner. The requirements for application of both methods are discussed.