Optical matrix processing: a review

Matrix multiplication is well suited to optical techniques, since the size of the matrix has no direct influence on the speed with which the multiplication takes place. Although iterative techniques have been developed to solve systems of linear equations, to find the eigenvectors of matrices, and to perform other matrix manipulations, research has been hampered somewhat by a lack of fast two-dimensional spatial light modulators (SLMs). Advances in SLM technology are discussed, and different architectures for matrix processing are reported. Acoustic Bragg cells, liquid crystal devices, magnetooptic devices and silicon/PLZT crystal light modulators are briefly reviewed. Both Systolic and fully parallel optical vector-matrix multiplier configurations are described. Iterative optical processors and bimodal (analog-digital) optical computer accuracy are briefly considered