Abstract
Calculation methods of simplifying interference fringe computation were proposed for Fresnel CGHs used two-dimensional image data. The interference fringes of the CGH are the superposition of many Fresnel zone plates. As these interference fringes form parallel patterns, there is much redundancy in the CGH. If we consider this property, we need not to calculate all points of the CGH. We may calculate the interference fringes of the CGH only at regular intervals. Although a dark ghost image is generated from this CGH in numerical image reconstruction, this ghost image does not affect to check the quality of a reconstructed virtual image. Therefore, the proposed methods are useful to decrease computation time of the interference fringes in computer simulation.
