Response of diffuse reflectance light of two-layered tissue to optical properties of inner layer

Although measurement of diffuse reflectance light can be used to determine the optical properties of tissue noninvasively, great effort should be firstly devoted to the development of the relation between the reflectance and optical properties of tissue in our opinion. In this paper, light diffuse reflectance by a tissue optical model with two-layered structure is discussed by use of Monte Carlo method. The distribution of diffuse reflectance vs. emitting angle at different optical properties of inner layer is calculated. In addition, the influence of the changing absorption coefficient, scattering coefficient of the inner layer on the light diffuse reflectance from the surface is investigated and analyzed. The simulation results show that the diffuse reflectance light is sensitive greatly to micro-change of optical properties (absorption coefficient and scattering coefficient) of the inner layer which has small value of optical properties. We believe that the results will be useful for the development of determination the optical parameters of bio-tissue in vivo.