Improved hidden surface removal method for computer-generated alcove hologram

Abstract

We have investigated the floating image display, which named computer-generated alcove hologram. The viewing angle was enlarged by changing the shape of the computer-generated hologram from flat to semi-half cylinder. To employ the calculation method of the computer-generated rainbow hologram, the full color floating image which has the wide viewing angle is reconstructed. Since these computer-generated holograms have the wide viewing angle, the correct hidden surface removal method is required. In our previous work, the computer-generated hologram was calculated by using the large number of object data from different viewpoints. When the fringe pattern was calculated, the calculation area is divided into small segments, and each small segment is calculated from one object data. The reconstructed image of the computer-generated hologram should not show the hole or overlap on the different viewing position. The small segment needs the several viewpoints information, especially the reconstructed image is close to the hologram plane. Therefore, the reconstructed image of the previous computer-generated hologram is concerned about the possibility of the hole or overlap. In this paper, we have proposed the improved hidden surface removal method which uses the virtual window. The calculation area, which is determined by the virtual window, is added to the object data. To apply the improved hidden surface removal method, we have achieved the more correct reconstructed image.