In the recent years, a number of methods have been developped to overcome the limitations of the classical coherent and incoherent image processing methods. A review of the main trends in this area is presented, indicating the principles of low-noise coherent processing, of incoherent processing of complex quantities and of white light processing ; it is seen that optical processing can now in a number of cases perform nonlinear operations, or shift invariant operations while still keeping the advantage of parallelism.
Pierre Chavel, Pierre Chavel,
"Optical Image Processing In Coherent And Incoherent Light: A Short Comparative Review", Proc. SPIE 0369, Max Born Centenary Conf, (16 June 1983); doi: 10.1117/12.934406; https://doi.org/10.1117/12.934406