PURPOSE: To make titled hologram approximate to a Fourier conversion hologram prepared by an optical system since the area distribution of a dot on the hlogram is equivalent to the variable density distribution of intensity of a composite wave and also a reference wave is used by recording the dot with high density.

CONSTITUTION: An input device 2 inputs to a CPU1 a coordinate and the reflection factor of a sample point on a plane preparing the hologram. The CPU1 executes operation processing by use of an inputted data. A coefficient showing the intensity of a reference wave is decided easily by simulation. An output device 3 contains a dot recording device of an XY plotter, etc., and is controlled by the CPU1. The inside of a recording area of recording paper is divided into picture elements corresponding to the sample point, and a dot of an area corresponding to its size is drawn. The recording paper recording a composite wave intensity data is reduced onto a negative or positive film by the technique of photograph copying to obtain the hologram. Since the reference wave is used, this hologram can be made approximate to the Fourier conversion hologram using the optical system.