Phase-only photorefractive joint transform correlator

In this work we propose a method to improve the discrimination capability of joint transform correlators. The technique is mainly developed to apply in photorefractive joint transform correlators that use a liquid crystal spatial light modulator to display the input plane and a BSO crystal to record dynamically the joint transform plane. The discrimination capability of the system is increased by using a phase-encoded input in combination with the phase-only information of the reference. To this end we use the liquid crystal modulator working in a pure phase mode. We perform numerical simulations to show that the proposed method also improves the discrimination capability of correlators with conventional linear detection of the joint power spectrum. Experimental results obtained with our photorefractive correlator are shown.

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