[OPTICAL REVIEW Vol. 9, No. 6 (2002) 251-254]
Full Color Computer-Generated Rainbow Hologram with Enlarged Viewing Angle
Hiroshi YOSHIKAWA* and Akihito KAGOTANI†
Department of Electronics and Computer Science, Nihon University, 7-24-1 Narashinodai, Funabashi, Chiba 274-8501, Japan
(Received December 19, 2001; Accepted August 12, 2002)
The viewing angle of a computer-generated hologram (CGH) can be expanded by lens-less Fourier configuration. However, a laser is required to illuminate the CGH for reconstruction. We proposed earlier making a second hologram for white-light reconstruction; here, we propose a method to calculate CGH for a full-color rainbow hologram with enlarged viewing angle. First, we calculate the master hologram with three virtual slits whose positions correspond to red, green and blue wavelength. The transfer hologram can be made from the master CGH with a single exposure. In the experimental result, we obtain a full-color computer-generated rainbow hologram with 17° of viewing angle and 3.0 mm × 2.5 mm image size.
Key words: holography, computer-generated hologram, enlarged viewing angle, full color, rainbow hologram