REAL-TIME OPTICALLY PROCESSED FACE RECOGNITION SYSTEM BASED ON ARBITRARY MOIRE CONTOURS

We demonstrate a hybrid electronic-optical real-time system that perfo rms 3-D face recognition, We constructed custom reference gratings tha t formed a desired moire pattern when mixed with images of structurall y illuminated faces. The moire patterns could be in any form such as, equal depth contours, error maps, or any arbitrary pattern. We demonst rate video methods to generate such error maps in real time, thus deve loping a real-time automated face recognition system based on the opti cal processing of arbitrary moire contours. We chose the moire pattern to be in the form of a Fresnel zone plate, which is displayed on a li quid crystal television. Illumination of this zone plate with parallel coherent light results in a diffracted beam that produces a focused l ine on a detector. For the matching process, the focal line is compare d against a preset threshold. If the confidence is above the threshold , the face is recognized, otherwise it is not. (C) 1996 Society of Pho to-Optical instrumentation Engineers.