Nonstationary image-plane speckle statistics
Gilbert V. April, Henri H. Arsenault · Journal of the Optical Society of America A · 1984
The properties of the image of a nonuniform transparency degraded by speckle noise are studied. Attention is focused on the spatial details of an object that cannot be resolved by a coherent system. Analysis of the power spectrum of the noisy spatial-intensity distribution in the image plane confirms that the bandwidth for coherent diffuse illumination corresponds to the incoherent transfer function of the system. Experimental verification is presented using a Ronchi ruling as a test object.