Speckle reduction in optical coherence tomography by strain compounding.

We present a speckle reduction technique for optical coherence tomography based on strain compounding. Decorrelation is introduced between B-scans by altering the sample's strain. A theoretical description of the technique, based on a transfer-function formalism, and experimental results on silicone phantoms are presented. Nearly complete decorrelation between successive B-scan speckle patterns was observed for a variation in strain of 0.045. Strain compounding by averaging nine B-scans, with 0.003 strain increments between them, resulted in a 1.5-fold reduction in speckle contrast ratio.