A novel way of noise reduction in image amplification by two-beam coupling in photorefractive BaTiO3 crystal

Abstract A scheme is described for removal of beam fanning, which is noise in the amplified image, by two-beam coupling in a photorefractive BaTiO 3 crystal. The large time constant of the beam fanning is exploited for the success of this scheme. An 8 ms duration pump pulse is used to read out the already formed photorefractive gratings to achieve a high quality amplified image with no beam fanning. Experimental results are given for comparison between the quality of the amplified image in this pulse read-out scheme and that of the conventional cw read-out scheme.

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