Real-Time Display Of 3-D Computer Data Using Computer Generated Holograms

In this paper we discuss two "real-time" (turn around times of a few seconds up to a minute) systems for display of three dimensional computer data using computer generated holograms. In one system the computer generated hologram is written on a high-resolution CRT in contact with a liquid crystal light valve. The liquid crystal light valve modulates a coherent, collimated, polarized readout beam with the data that is displayed on the CRT. The modulated beam is then used to reconstruct the object that had been encoded in the hologram on the CRT. In the second system the computer generated hologram that had been displayed on the CRT is imaged and recorded on a thermoplastic plate. The developed thermoplastic plate can then be used to reconstruct the object with a coherent beam.