Abstract

In this presentation, we describe a technique to represent gray scale filters in a binary format such that both the magnitude and the phase of the filter function are preserved.^1,2 We show how this technique is applied to represent kth-law nonlinearly transformed matched filters in a binary format. A linear matched filter function is binarized by using a multiple level threshold function to implement the gray scale filter. By selecting a proper threshold function to binarize the matched filter function, the first order correlation signal produced by the binary encoded matched filter becomes equivalent to the first order correlation signal produced by the gray scale nonlinearly transformed matched filter. The binary encoded matched filter function can be written onto a binary SLM in the Fourier plane, and the need for a gray scale SLM is eliminated. Optical experiments and computer simulation tests using the binary encoded filters are presented.

© 1992 Optical Society of America