  Optical coherence tomography (OCT) is a powerful biomedical imaging
technology that relies on the coherent detection of backscattered light to
image tissue morphology in vivo. As a consequence, OCT is susceptible to
coherent noise (speckle noise), which imposes significant limitations on its
diagnostic capabilities. Here we show a method based purely on light
manipulation that is able to entirely remove the speckle noise originating from
turbid samples without any compromise in resolution. We refer to this method as
Speckle-Free OCT (SFOCT). Using SFOCT, we succeeded in revealing small
structures that are otherwise hidden by speckle noise when using conventional
OCT, including the inner stromal structure of a live mouse cornea, the fine
structures inside the mouse pinna, sweat ducts, and Meissners corpuscle in the
human fingertip skin. SFOCT has the potential to markedly increase OCTs
diagnostic capabilities of various human diseases by revealing minute features
that correlate with early pathology.
