Diffuse illumination in holographic double-aperture interferometry.

It is experimentally shown that the diffuse illumination in holographic interferometry influences the visibility function of the fringes and, as a result, the fringe contrast depends on the fringe order. This property can be applied to identification of the local minima of fringe order in double-exposure holographic interferometry. The method has been used in identifying the nodal pattern of a singer’s skin vibrations in double-pulse holographic interferometry.