Research on refractive index distribution in biological tissues

Abstract

From the view of refractive index distribution, biological tissue can be regarded as a refractive index random media. Inhomogeneous distribution of refractive index is the physical basis of the high scattering property of biological tissue, whose scale is close to wavelength. Disperse scatter model and statistical distribution function are introdcued to describe the refractive index distribution in biological tissues such as blood tissue. Based on the disperse scatter model and scatter theory, the relations between refractive index fluctuation and scattering coefficient of biological tissue are derived and corresponding formulas are given to calculate the refractive index fluctuation in biological tissue. The formulas are applied to calculate the refractive index distribution of blood tissue in different status, combining the Rayleigh scattering describing the single scattering events. The calculating results are illustrated in the paper.