Systematic errors of an optical encryption system due to the discrete values of a spatial light modulator
Unnikrishnan Gopinathan · Optical Engineering · 2009
An optical implementation of the amplitude encoded double random phase encryption/decryption technique is implemented, and both numerical and experimental results are presented. In particular, we examine the effect of quantization in the decryption process due to the discrete values and quantized levels, which a spatial light modulator (SLM) can physically display. To do this, we characterize a transmissive SLM using Jones matrices and then map a complex image to the physically achievable levels of the SLM using the pseudorandom encoding technique. We present both numerical and experimental results that quantify the performance of the system.