Optical reflection tomography along the geometrical thickness

Very recently, we proposed and demonstrated a novel optical reflection tomography along the geometrical thickness, reflecting a real cross-sectional structure of an object. This technique is based on simultaneous measurement of refractive index n and thickness t of a sample using the combination of a low coherence interferometer and confocal optics. The interferometer provides optical coherence tomography (OCT) of the dimension of the optical thickness (= nXt) dong the optical axis, while the confocal optics gives us another type of reflection tomography, having the thickness dimension of nearly t/n dong the optical axis. This tomography can be called confocal reflection tomography (CRT) and has not yet been demonstrated, to our knowledge. Simple image processing of OCT and CRT results in desired reflection tomographic image, showing two-dimensional refractive index distribution dong the geometrical thickness. In this paper, we present the validity of our proposed method using the concave glass plate as well as the application for in vivo measurement of biological tissue.