Photorefractive multichannel correlator based on stoichiometric LiTaO[sub 3].

Abstract. We demonstrate a Vander Lugt type correlatot based on photorefractive stoichiometric LiTaO[sub 3] as the volume holographic material. Accurate correlator output was obtained for binary phase-modulated input images. The correlator is tested with binary amplitude- and phase-modulated input images. Phase-modulated images show a high-quality correlation, whereas amplitude-modulated images suffer in part from a photorefractive self-focusing effect. Using 100 previously stored holograms as filters, a rate of 10 000 correlations/s are demonstrated. A paraxial theoretical analysis of the correlator, giving analytic expressions for the shift invariance, is also described in detail. [ABSTRACT FROM AUTHOR]