IMPLEMENTATION OF ARBITRARY REAL-VALUED CORRELATION FILTERS FOR THE SHADOW-CASTING INCOHERENT CORRELATOR

We describe an incoherent correlator, based on the shadow-casting prin ciple, that is able to implement any real-valued linear correlation fi lter. The correlation filter and the input image are displayed on comm ercial liquid-crystal television (LCTV) panels. Although it cannot han dle high-resolution images, the incoherent correlator is lensless, com pact, low cost, and uses a white-light source. A bipolar technique is devised to represent any linear filter, computed from a single referen ce image or composite, in the correlator. We demonstrate experimentall y the efficiency of the design in the case of optimal trade-off (OT) f ilters and optimal trade-off synthetic discriminant function (OT-SDF) filters. (C) 1996 Optical Society of America