Design of partial information filters for optical correlators

Very efficient suboptimal algorithms for the design of phase-only filters (POFs) and binary-phase-only filters (BPOFs) are presented. A reduction of 2 to 3 orders of magnitude in computer time is obtained over previous algorithms. The loses in signal-to-noise ratio is negligible (less than 0.001 dB). The authors have implemented and tested the new algorithm with excellent results. In their computer simulations they used the 32 by 32 gray level tank image. To compute the OPOF, the tank image is zero-padded and a 64 by 64 FFT is performed