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Modeling and correction of incoherent wavefront distortion

There are two types of wavefront distortion inside the female breast: incoherent scattering and coherent interference. Adaptive wavefront compensation algorithms developed so far are useful for correction of incoherent distortion caused by scattering. The performances of these algorithms differ according to the extent of wavefront amplitude distortion. It is shown analytically and experimentally in this article that the matched filtering approach, while optimal for detection, is not so for imaging when the wavefront amplitude is distorted in addition to phasefront distortion. Matched filtering algorithms increase wavefront amplitude variance and therefore decrease image contrast. The inverse filtering approach, while ideal for fidelity, is not stable when the signal‐to‐noise ratio is low. An approach toward inverse filtering, amplitude compression operation in addition to phase deaberration, is introduced in this article. Analysis and experiments show that its performance is superior to matched filtering algorithms and to time‐delay type correction algorithms without introducing stability problems. © 1996 John Wiley & Sons, Inc. Int J Imaging Syst Technol, 8, 322–335, 1997