Abstract

Correlation methods play an important role in optical information processing and pattern recognition. In some applications, however, the light efficiency of optical correlators is not sufficient. Recent works have shown that the problem may be avoided by using one of several types of pure phase filter. One type of phase-only filter was proposed by Homer and Gianino,¹ another one, the tandem component filter by Bartelt.² These results initiated a series of studies analyzing the possibilities of more complicated, both continuous and binary, phase-only filters. There are several advantages of restricting the filter function to binary values only. This approach is particularly useful for real-time applications with spatial light modulators.

© 1988 Optical Society of America