NONREDUNDANT CALCULATIONS FOR CREATING DIGITAL FRESNEL HOLOGRAMS

In this paper we propose an alternative technique for producing digita l Fresnel holograms. The evaluation of a diffraction pattern in a wide region is implemented in such a way as to avoid redundant calculation s and preserve the precision. Because of the symmetry of the kernel, t he complex amplitude is calculated at four points in the registration plane simultaneously. This algorithm decreases the required CPU time 4 times with respect to direct calculation. The digital Fresnel hologra m is numerically and optically reconstructed, and some qualitative com parisons are made. (C) 1997 Optical Society of America.