MULTIPLE-SCATTERING IN OPTICAL COHERENCE MICROSCOPY

We show that the multiple-scatter rejection provided by optical cohere nce microscopy (low-coherence interferometry) can be incomplete in opt ically turbid media and that multiple scattering manifests itself in t wo distinct ways. Multiple small-angle scattering results in an effect ive probe field that is stronger than expected from a first-order beam extinction model, but that contains a distorted wave front that enhan ces the apparent reflectance of small structures relative to those tha t are larger than the unscattered incident beam. Multiple wide-angle s cattering produces a broad diffuse haze that reduces the contrast of s ubsequent features.