Tam W G, Zardecki A
Appl Opt. 1980 Aug 15;19(16):2822-7. doi: 10.1364/AO.19.002822.
The role of non-small-angle scattering is examined for off-axis laser beam propagation under low visibility weather conditions. The near-axis radiance distribution function is obtained from a radiative transfer equation with the aid of the small-angle approximation. The contribution of the non-small-angle scattering is described via another transfer equation with the on-axis radiance as an external source, and this equation is solved in the diffusion approximation. Numerical results for radiational and advective fogs are presented to show the importance of non-small-angle scattering in the case of off-axis detection.
研究了在低能见度天气条件下非小角散射对离轴激光束传播的作用。借助小角近似从辐射传输方程获得近轴辐射率分布函数。非小角散射的贡献通过以轴上辐射率为外源的另一个传输方程来描述，并且该方程在扩散近似下求解。给出了辐射雾和平流雾的数值结果，以表明在离轴探测情况下非小角散射的重要性。
