Compact parallel joint transform correlator for facial recognition

We discuss the design of a compact parallel joint transform correator (PJTC) using four binary zone plate array (BZPA) as a Fourier transform lens. The external dimensions of the hybrid opt-electronic correlator is 23 cm x 15 cm x 16.3 cm, which includes the PJTC system in the upper stage and some of driving circuits and an LD for a light source in the lower stage.: Experimentally, we implemented this compact PJTC system for facial recognition with database of 100 persons and obtained reliable discrimination results. Furthermore, we propose a novel method of pre-processing so that any general users could easily operate the compact PJTC system and constantly obtained the same size extracted images, by fixing three points; the:edges of both eyes and the low end of nose, when normalizing the facial image size. We confirmed the ability of our system to meet the conditions for recognition by JTC.