A study on optimal pattern recognition filters implementable on spatial light modulators with annular response regions

Studies on optical pattern recognition filters concern the use of spatial light modulators (SLMs) having unconstrained response regions or infinite contrast ratios. In this paper, constrained optimal saturated filters (SFs) are designed to accommodate two dimensional SLMs having annular response regions with finite contrast ratios. The signal-to-noise ratio (SNR) is used as the performance criterion in evaluating the performance of these filters. A further study is made on optimal saturated filters (OSFs) with multiple response regions and suboptimal saturated filters (sub-OSFs). Simulation results are also given