Effect of optical aberration on Gaussian speckle in a partially coherent imaging system.

Optical aberration effects on Gaussian speckle contrast are theoretically examined in an imaging system exhibiting partial spatial coherence. Analysis includes phase-perturbed random fields from a rough object illuminated by an extended source that generate speckle in the image plane. Results indicate that, unlike coherent illumination, speckle contrast in this partially coherent system depends on odd-functional aberrations, such as coma. In addition, calculations show that speckle contrast reduction as a function of coherence factor exhibits a stronger dependence on aberrations than for an aberration-free case.