Full Color Computer-Generated Rainbow Hologram with Enlarged Viewing Angle

ABSTRACT (Presented SPIE Photonics West 2001, SPIE Proceedings Vol. 4296, Paper # 4296A-25, Jan. 2001.)

The viewing angle of the computer-generated hologram (CGH) can be expanded with lens-less Fourier configuration. It, however, requires a laser to illuminate the CGH for reconstruction. In the previous paper, we have proposed that making the second hologram for white-light reconstruction. The reconstructed image from the first hologram is used as the object beam of the second hologram. The second hologram can be either transmission or reflection hologram, which depends on the direction of the reference beam. In this paper, we propose a method to calculate CGH for the full-color rainbow hologram with enlarged viewing angle. First, we calculate the master hologram with three virtual slits whose positions are corresponding to red, green and blue wavelength. The transfer hologram can be made from the master CGH with single exposure. In the experimental result, we obtain full-color computer-generated rainbow hologram with 17 degrees of viewing angle and 3.0 mm x 2.5 mm image size.