Optical technology has emerged as a viable solution to the growing demand to increase the throughput of high speed processors and computers. Although higher speed and denser integrated circuits are being developed, it appears that faster switching speeds in digital circuits will not provide an adequate solution to the bottleneck problem of computing systems for such tasks as real-time distortion-invariant pattern recognition and associative memory. Even supercomputers using new computing architectures and subnanosecond gate delays do not have sufficient speed for such real-time operations. Optical systems offer the advantages of inherent parallelism and high speed with superior interconnection capability, which allow for the processing of millions of simultaneous operations. The lack of electromagnetic interference in optics is ideally suited for neural network based proces-sors, which require a high degree of interconnectivity and global communications properties. Analog optical computers are particularly attractive for the processing of large stochastic data, while the more precise digital computers break down when confronted with such random problems. The immunity to electromagnetic interference can also be used advantageously in VLSI interconnections technology and board-to-board communications to reduce the pinout problem and to improve flexibility and performance. For these reasons, optical technology has become a major research and development effort at many industrial, government, and university laboratories both nationally and internationally.