A spatial light modulator (SLM) operating as an amplitude modulating input element in a coherent optical correlator introduces a certain amount of phase shift at each pixel. We examine the effect this has on the overall quality of the correlation signal, defined in terms of SNR and correlation peak full-width-half-maxi-mum (FWHM) response. An interesting and unexpected effect is found, namely that if the attendant phase distortion is properly incorpored into the reference function, it can greatly enhance the correlation signal.
Joseph L. Horner,
"Slm Inducd Phase Distortion And Its Effect On Optical Correlation", Proc. SPIE 0754, Optical and Digital Pattern Recognition, (21 August 1987); doi: 10.1117/12.939980; https://doi.org/10.1117/12.939980