We demonstrate a hybrid electronic-optical real-time system that performs 3-D face recognition. We constructed custom reference gratings that formed a desired moire pattern when mixed with images of structurally illuminated faces. The moiré patterns could be in any form such as, equal depth contours, error maps, or any arbitrary pattern. We demonstrate video methods to generate such error maps in real time, thus developing a real-time automated face recognition system based on the optical processing of arbitrary moiré contours. We chose the moiré pattern to be in the form of a Fresnel zone plate, which is displayed on a liquid crystal television. Illumination of this zone plate with parallel coherent light results in a diffracted beam that produces a focused line on a detector. For the matching process, the focal line is compared against a preset threshold. If the confidence is above the threshold, the face is recognized, Otherwise it is not. © 1996 Society of Photo-Optical Instrumentation Engineers. © 1996 Society of Photo-Optical Instrumentation Engineers.
Andrade, R. A. (1996). Real-time optically processed face recognition system based on arbitrary moiré contours. Optical Engineering, 35(9), 2534-2540.