Form-factor of the holograms of composite images

This article is a follow-on study of the influence of the form-factor of holograms on their optimal characteristics, such as the optimal exposure, subject to a known visibility distribution, and the maximum achievable values of the average diffraction efficiency in a hologram. The main attention is paid to the verification of the applicability of the form-factor concept to calculating the optimal parameters of a phase hologram. The results obtained suggest that the technique of calculation and practical use of the form-factor is suitable for holograms of real images formed by complex beams. Using 30-plus real images, the approach to determining the form factor for visual holograms is analyzed. A fairly good agreement between the form factors of the holograms of real portrait images and those of Gaussian beams has been found. The real images have been shown to have near-Gaussian brightness distribution statistics. Note that for non-Gaussian distributions, the proposed method of calculating and using the form-factor is also suitable.