The binary phase-only 1/f joint transform correlator

In this paper we present a new approach to implementing the joint transform correlator based on a single ferroelectric spatial light modulator used as a binary phase-only device. The correlator is a 1/f joint transform correlator which uses two passes through the optical system to generate the peaks. The input scene and reference image are encoded with a chequerboard pattern to produce a spectrum with no zero order. The spectrum is then convolutionally binarised and replayed on the spatial light modulator. Experimental results demonstrate strong correlation peaks with a zero order in the correlation plane reduced to 6dB below the correlation peaks. The correlator also demonstrates enhanced differentiation between closely correlated images.