Optical correlators with fast updating speed using photorefractive semiconductor materials.

An updatable optical correlator which uses a photorefractive compound semiconductor to generate real-time matched filters is proposed. Using compound semiconductors offers high speed with low optical input intensities. Here we discuss issues affecting the performance of this correlator. This includes an analysis of the Bragg diffraction and a discussion of the speed and power considerations of these materials. Experimental results obtained using photorefractive GaAs are also presented.