EXPERIMENTAL IMPLEMENTATION OF A JOINT TRANSFORM CORRELATOR USING SYNTHETIC DISCRIMINANT FUNCTIONS

A joint transform correlator (JTC) was implemented in the Optical Scie nce Department at CERT. In order to ensure a rotational invariance, th e reference image is replaced by a synthetic discriminant function (SD F) image displayed on an amplitude spatial light modulator (SLM). Nume rical simulations are performed and then compared to experiments. We s how that the pseudo-inverse SDF (PI-SDF) gives accurate experimental r esults. The training ability of the PI-SDF allows it to recognize the reference object unambiguously, even if the input view does not explic itly belong to the training set. Then, we propose to replace our ampli tude device with a ternary phase and amplitude device, in order to dis play positive and negative images: this allows us to display any kind of SDF filters, e.g. OT-SDF or MINACE-SDF, which reduce the side lobes , with a good resistance to noise.