Morito Morishima

Computer-generated holograms on a CD-R disk

In order to display three-dimensional imagery by computer-generated holograms, it is necessary to draw hologram data on a medium with a resolution on the micrometer order. Conventionally, optical lithography, electron beam lithography, and special laser beam printers designed especially for holograms are used. However these systems are large and expensive, and need special environments such as darkrooms and clean rooms. We have developed a new device that draws hologram data on CD-R (Compact Disc-Recordable) disks, and which is based on a Yamaha CRW-F1 CD-R/RW drive. The drive produces holograms in a short amount of time, at low cost, and at the high resolution of 1.5μm. Moreover, the drive is small, portable and does not require a special environment, so that all of the processes of Desktop Holograming, from hologram calculation to recording, are made possible with just one PC. We evaluated optical properties of the CD-R disk as a viable hologram recording media. There are characteristics that are different from conventional media, because hologram data is recorded on spiral shaped grooves. We propose a new calculation method of hologram data suitable for a CD-R disk in order to display three-dimensional imagery. Using this method, we carried out optical experiments and it showed reconstructed three-dimensional imagery on CD-R disks successfully. In this paper, we discuss the optical properties of the CD-R disk, calculation method, and the experimental results.