The application of impulse response function in Monte Carlo simulation of light distribution in biological tissues

Monte Carlo method is the only effective solution in the study of light distribution in biological tissues irradiated by a complex surface source. However,direct Monte Carlo simulation demands large computational capacity because of its low rate of convergence.In this paper,the concept of impulse response function in biological tissues is introduced,thus light distribution in certain depth of the biological tissue can simply be obtained by calculating the convolation of incident source function and the impulse response function. On the basis of computer simulation,a criterion is proposed to evaluate the results of Monte Carlo simulation. By means of the criterion,the influence of impulse response function and dispersed quantity of the light source is analysed comprehensively,which shows that the calculating efficiency is greatly improved by the introduction of impulse response function in Monte Carlo simulation of light distribution in biological tissues.