Speckle variance optical coherence tomography using an SS-OCT system and an extended k-sampling clock

is vacant or filled with material having a refractive index different from the tissue, the observed structure is deformed significantly. This deformation artifact can be minimized by filling the cavity with liquid having a refractive index nearly equal to the tissue. Furthermore, by using dynamical OCT method, cavity image intensity can be significantly enhanced compared with the tissue. This image contrast improvement may allow imaging of cavity structures inside deep in tissues. In this paper, we demonstrate good contrast of speckle variance OCT imaging of phantoms. A trial of deep OCT imaging is introduced with which we can extend the OCT depth range to 27.5 mm with a commercial swept source, while the preinstalled k-clock allows only the OCT depth range of 5 mm.