An improved Monte Carlo diffusion hybrid model for light reflectance by turbid media

This paper introduces an improved diffusion model which is accurate and fast in computation for the cases of mu(a)/mu'(s) < 0.07 as good as the conventional diffusion model for the cases of mu(a)/mu'(s) < 0.007 for surface measurement, hence more suitable than the conventional model to be the forward model used in the image reconstruction in the diffuse optical tomography. Deviation of the diffusion approximation (DA) on the medium surface is first studied in the Monte Carlo (MC) diffusion hybrid model for reflectance setup. A modification of DA and an improved MC diffusion hybrid model based on this modified DA are introduced. Numerical tests show that for media with relatively strong absorption the present modified diffusion approach can reduce the surface deviation significantly in both the hybrid and pure diffusion model, and consumes nearly no more computation time than the conventional diffusion approach.