Statistical analysis of interferometric imaging system with rotating diffuser

The theoretical model of signal-to-noise ratio(SNR) in the interferometric imaging system with rotating diffuser is proposed by means of statistical optics. According to the theoretical model, the relations between parameters of rotating diffuser, coherent time and SNR of the imaging system are analyzed numerically and demonstrated experimentally. It is shown that the rotating diffuser reduces coherent time, increases the number of unrelated speckle noises in gathering time, and thus reduces the speckle noise. An increasing in roughness or rotating frequency of diffuser or a decreasing in coherent length leads to a decreasing in coherent time. To obtain high SNR, the rotating diffuser should be well controlled so that the rotating period is approximately equal to the exposure time of CCD,