Optimal pupil screen design for the estimation of partially coherent images

The effectiveness of optical preprocessing is examined for image-estimation applications. The problem is to design the pupil of the imaging system so that the detected image is the minimum-mean-square-error estimate of the desired image. The designs of several optimal pupil screens are presented. These designs demonstrate that both the optimum pupil screen and the effectiveness of optical preprocessing are functions of the statistics of the signal and the noise and of the coherence of the object illumination. The results indicate that preprocessing is more effective for coherent systems than for incoherent systems.