An overview of optical signal processing techniques

Optics applications in signal processing, principally fiber optics for low loss data transmission, and acousto-optics in spectrum analysis are reviewed. In each case the performance of the optical device greatly surpasses that of alternative technologies. The principal limitations of most other applications of optics concern their accuracy and dynamic range, and the problem of interfacing with electronics. The most obvious and important problem concerns the nonavailability of a cheap, reliable, reproducible spatial light modulator. This precludes the exploitation of many two-dimensional optical processors. The attraction of all-optical computing is boosted by the problems encountered in VLSI, although it is likely to be many years before such devices seriously compete with digital electronics.