FORMATION OF HOLOGRAM INFORMATION

PURPOSE:To decrease the quantity of calculation at the time of determining hologram phase distributions relating to the method for forming hologram information capable of making natural stereoscopic display by using an electronic device. CONSTITUTION:A hologram plane 10 which expresses the phase distribution, a visible area where stereoscopic images are visible and stereoscopic display limits 30, 32 are set in a virtual space and the object to be stereoscopically displayed is expressed in the virtual space by the set of micropolygonal shapes. Plural slicing planes 18 parallel with the horizontal plane are set in the virtual space including the object and the segments intersecting with the polygonal shapes are determined with each of the slicing planes 18. The detected segments are divided or clipped at need and are extracted by dividing these segments to the parts always visible from the entire area 26 of the visible region and the parts visible only from a part of the visible area 26 by being hindered by other segments in the final. The calculation of the phase distribution is executed by setting sampling points at the extracted segments and calculating the one-dimensional phase distribution on the hologram plane at every sampling point. The calculated one-dimensional 12 hologram phase distributions are added for each of the same slicing planes 18.