The paper discusses briefly the commonly used description of the speckle phenomenon, pointing out that it is correct, strictly speaking, only as a limiting case. A more general model is proposed, based on the properties of entire functions of exponential type, this being the logical extension of the Fourier approach to optics. The conclusion is that speckle is the inevitable physical manifestation of the distribution of (complex) zeros of such functions. The modification of the distribution of zeros by filtering is discussed, and this is illustrated.