OPTICAL CORRELATOR PERFORMANCE USING A PHASE-WITH-CONSTRAINED-MAGNITUDE COMPLEX SPATIAL FILTER

Certain kinds of spatial light modulators (SLMs) can be used in a mode where the phase transmittance at a given point has the desired value, measured modulo-27r, and the magnitude transmittance has approximately the desired value. Computer simulations, based on a specific model of a deformable-mirror SLM, show that these phase-with-coupled-magnitude SLMs perform better for the particular cases studied, in terms of discrimination and signal-to-clutter ratio, than phase-only and binary phase-only SLMs in coherent optical pattern-recognition correlators where the input is distorted by variable illumination, rotation, and noise relative to the template pattern. © 1990 Optical Society of America.