Real-time computer-aided multiplexed optical intensity correlator using Fresnel holographic filters and a liquid crystal television

A real-time computer-aided optical intensity correlator using multiplexed Fresnel holographic filters (FHFs) and a liquid crystal television (LCTV) is described. This technique is characterized by the following. The spatially separated multichannel filters are fabricated by a single exposure holographic recording; the multiplexed optical correlator is simple in structure with low alignment requirements; the spatial phase variation existing inherently in the LCTV has no influence on the correlation pattern and the system has a higher discrimination by means of computer preprocessing. Several experimental results are presented.