为研究光子在高散射媒质中的传输特性,将高散射媒质等效为离散的球形散射体集合。在蒙特-卡罗方法的基础上,提出一种新的椭圆算法来确定高散射媒质中散射点的分布。根据米氏散射理论和光子辐射输运方程,结合模拟解析得到的散射点的分布,不同粒径、不同光程下光子散射阶数的分布以及不同散射阶数的散射光强分布,从而实现光子在高散射媒质中动态特性的数值解析。数值解析结果表明光子在高散射媒质中的传输过程本质上是光子的复散射过程,这种数值解析方法能有效解析高散射媒质中光子从单散射到复散射全光程的动态传输特性。
The discrete equivalent spherical scatterers aggregate model is developed to investigate the photon′s transport characteristics in highly scattering media.Based on Monte-Carlo method,we propose a new ellipse algorithm to determine the scattering point distributions.According to Mie theory and the radiative transfer equation,combined with the obtained scattering point distributions,path-length dependent scattering order distribution and scattering intensity in different scattering orders with different particle sizes are numerically calculated.The results show that the photon's transport in highly media is essentially a multiple scattering process.The numerical algorithm can be used effectively to analyze dynamic scattering properties of scattered light from single-scattering to multiple-scattering regime.