Diffraction efficiency of three-dimensional phase hologram of diffuse object

The diffraction efficiency of the hologram of a diffuse object is analyzed within the framework of a space-frequency approach in which the diffraction efficiency is expressed through the spectrum of the wave recovered by the hologram. The diffraction efficiencies and the expsoures needed to achieve them are shown to be a function of the relationship between the intensities of the interfering beams, and the geometry of the hologram recording scheme. It is recommended that oblique incidence of the reference wave be employed in recording the hologram of the object. The angle of incidence of the object wave should consider that the hologram efficiency decreases as the angle becomes smaller, but that the exposure level needed to obtain maximum efficiency becomes somewhat longer.