Real-time computation of diffraction fields for pixelated spatial light modulators.

Abstract

Fast calculation of diffraction field from a three-dimensional object is an important problem in holographic three-dimensional television. As a result of this, several fast algorithms can be found in the literature, but most them omit pixelated structure of the display device used in the reconstruction process. We propose a fast algorithm for diffraction field calculation from a three-dimensional object for a pixelated display device. Real-time calculations can also be achieved when the proposed algorithm is run on a graphical processing unit. Performance assessment of the algorithm is obtained by the computation time of the diffraction field and the error on the reconstructed object. The proposed algorithm employs a precomputed look-up-table which is formed by one-dimensional kernels. Each kernel in the look-up-table denotes a diffraction field on the display device from a point light source at a specific depth along longitudinal axis. Allocated memory space by the precomputed look-up-table is optimized according to the sampling policy of the depth parameter. Look-up-table formed by uniformly sampled depth parameter provides the same error on the reconstructed object with less number of kernels. Also, optical experiments are conducted and successful results are obtained.