Numerical reconstruction of 3D image in Fourier domain confocal optical coherence microscopy

Abstract

Along with high longitudinal resolution of optical coherence tomography, confocal optical coherence microscopy (OCM) provides high transversal resolution due to relatively high numerical apertures. However, the presence of relatively high numerical apertures leads to limited depth of field, which reduces the speed of OCM and decreases the advantage of Fourier domain detection. In this paper we propose a numerical processing technique for three-dimensional image reconstruction in Fourier domain OCM. It takes into account not only the defocus of different parts of imaged volumetric sample, but also the effects of upper layers’ refractive index on imaging the sample inner structure. Besides providing sharp coherence gated imaging, this technique also allows for determining both the geometrical thickness and refractive index of the sample layers.