Real-time computer-generated hologram by means of liquid-crystal television spatial light modulator

A novel use of liquid-crystal television (LCTV) is described. It is shown that, if the phase nonuniformity of the LCTV is corrected by a liquid gate, then a simple computer-generated hologram can be written and coherently reconstructed. It is well known that spatial light modulators (SLM's) are essential for real-time optical information process-ing. For that reason, much research has been devoted to them, and many types of SLM have been devel-oped.1 Most of the existing SLM's are either forbiddingly expensive or still in the research and development stages. Recently an extremely inexpensive liquid-crystal television (LCTV) was investigated in relation to its use in optical data processing.2-10 One advan-tage of the LCTV is that it can be addressed either electronically or optically. However, because of th