离散坐标法在计算生物组织内光场空间角分布中的应用

从辐射传输理论出发,研究了准直光照下层状生物组织内漫射光场的角分布.在辐射传输方程的基础上,采用离散坐标法得到了描述层状生物组织内漫射光传输问题的微分方程组形式,并用特征值-特征矢量方法对其进行了求解,给出了通解形式.结合边界条件对两类典型生物组织内漫射光场角分布进行了数值计算-各向同性组织和前向散射组织,给出了组织内不同深度处漫射光场空间角分布曲线.通过对计算结果比较分析,得到了生物组织内漫射光场空间角分布随深度的变化规律,及边界效应和光学参量对组织内漫射光场空间角分布的影响.

Application of Discrete-ordinate Method in Calculation of Light Angular Distribution in Biological Tissues

Based on the radiative transfer equation, Discrete-ordinate method is used to calculate the diffuse light angular distribution in layered biological tissues irradiated perpendicularly by collimation light. A differential equation group is obtained, which can describe the diffuse light field in biological tissues. Eigenvalue-eigenvector method is adopted to solve the differential equation group, and its general solution is also given. According to the general solution, light angular distributions in two kinds typical biological tissues are calculated including isptropic tissue and forward scattering tissue. Curves of light angular distributions on planes of different depths in biological tissues are illustrated in the paper. According to the results, the characteristics of light angular distribution in tissues are analyzed and the effects of boundary effect and optical parameters on the angular light distribution are also discussed.