A modified condensed Monte Carlo simulation of reflectance with focus light beam from scattering medium

Condensed Monte Carlo (MC) methods were modified to predict the spatially-resolved reflectance from turbid medium with arbitrary scattering and absorption coefficients. The calculation was accelerated by direct scaling the radial reflectance of baseline simulation, which is more efficient than the photon-by-photon scaling method. We have demonstrated that the methods are valid for focus incident light as well as homogeneous single-layer turbid media. This approach was validated against a standard MC model with very low cost of time to the level of tens of microseconds.