Consideration on Sampling Interval in Computer-generated Hologram Using Angle Spectrum Method

A hologram is a recording medium created by holography that records and reproduces a three-dimensional object. Creating a hologram on a computer is Computer-generated holography, and a hologram created by computer holography is called a Computer-generated hologram.In this paper, the angular spectrum method which has short calculation time and can reproduce even in the short distance is used.Computer-generated hologram can be obtained by calculation on a computer, but the distribution of holograms is obtained by discrete values because computers can not handle continuous values.Therefore, sampling intervals must be taken into account. In this paper, we study and consider how the sampling interval affects when reproducing a hologram created by the angular spectrum method. As a result of the simulation, it was found that the pixel pitch has to be changed according to the distance of reproducing the hologram.