APPLICATIONS OF PHOTOREFRACTIVE VOLUME HOLOGRAPHY IN OPTICAL COMPUTING

Abstract

After a brief review of the photorefractive effect, we describe three examples of the applications in optical computing using photorefractive volume holography. These are 3-dimensional optical storage, parallel optical matrix processor, and multiwavelength optical half-adder. For the 3-dimensional optical storage, we consider some fundamental issues in photorefractive memory, including the storage capacity and the dynamic range. We also discuss the photorefractive noise gratings formed during a multiple exposure schedule. These fundamental issues in photorefractive storage are important in understanding the potentials and limitations of optical memory systems. For parallel optical matrix processing, we propose and demonstrate a novel method of matrix-matrix application using grating degeneracy in photorefractive media in conjunction with incoherent laser source arrays. For multiwavelength optical half-adder, we describe photorefractive logic gates and their application in the summation of binary numbers.