Source encoding, signal sampling and spectral band filtering for partially coherent optical signal processing

Abstract

Relations between coherence requirement, spectral filtering, signal sampling, and source encoding are discussed. Since the spatial coherence requirement is determined by the signal processing operation, a strict spatial coherence is usually not required. The advantage of the source encoding is to relax the constraints of a physical light source so that the signal processing can be carried out with an extended incoherent source. The effect of signal sampling is to improve the temporal coherence requirement at the Fourier plane so that the spatial filtering can be carried out with a partially coherence mode. The objective of broad spectral band filtering is to carry out the signal processing over the entire spectral band of the light source so that the coherent noise can be eliminated. Since the partially coherent optical processor utilizes a broad spectral band white-light source, it is particularly suitable for color signal processing. Experimental demonstrations for the source encoding, signal sampling and spectral band filtering are included.