Multiple scattering calculations for technology.
Multiple scattering calculations for technology.
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DOI：
10.1364/ao.10.001485
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发表时间：
1971-07
期刊：
影响因子：
1.9
通讯作者：
P. S. Mudgett;L. Richards
中科院分区：
文献类型：
--
作者：
P. S. Mudgett;L. Richards
一个多通量（离散坐标）辐射传输计算程序的目标是使数学容易学习和使用。主要的近似是忽略极化。不包括散射介质内的发射，并且公式仅限于由平行平面限定的散射介质。边界条件允许各种照明，并在散射介质的边界处的表面反射系数被准确地确定。与双通量（Kubelka-Munk）和四通量计算方法进行了比较，得到了这些简单理论中散射系数和吸收系数的经验表达式，使它们得到与精确理论几乎相同的结果。这些经验公式为混浊介质的绝对反射率和透射率的估算提供了一种非常简单的方法，大大提高了双通量和四通量计算方法的实用性。双通量方程给出了极好的结果，条件是与散射相比吸收较小，并且光学厚度大于5。与实验数据的比较表明，四通量方程在任何光学厚度，即使吸收是强的。
A many-flux (discrete ordinate) radiative transfer calculation procedure is described with the goal of making the mathematics easy to learn and use. The major approximation is the neglect of polarization. Emission within the scattering medium is not included, and the formulas are restricted to a scattering medium bounded by parallel planes. The boundary conditions allow for a variety of kinds of illumination, and the surface reflection coefficients at the boundaries of the scattering medium are accurately determined. A comparison is made with the two-flux (Kubelka-Munk) and four-flux calculation methods, and this leads to empirical expressions for the scattering and absorption coefficients in these simple theories, which make them give nearly the same results as exact theories. These empirical expressions provide a very simple method for estimating the absolute reflectance and transmittance of turbid media and greatly increase the utility of the two-flux and four-flux calculation methods. The two-flux equations give excellent results provided the absorption is small compared to scattering and the optical thickness is greater than 5. A comparison with experimental data taken with collimated illumination shows that the four-flux equations give good results at any optical thickness even if the absorption is strong.