Gordon H R, Xu X
Appl Opt. 1996 Jul 20;35(21):4194-205. doi: 10.1364/AO.35.004194.
The governing equations are developed for the marine asymptotic daylight field in the scalar approximation, including the effects of inelastic processes-Raman scattering and chromophoric dissolved organic matter fluorescence. The governing equations are solved numerically and compared with Monte Carlo simulations. It is found that these solutions are the actual radiance distributions approached by the asymptotic field in the Monte Carlo simulations. Sample solutions are provided to show the sensitivity of the light field to the various parameters of the medium. For certain values of the parameters, inclusion of inelastic processes can drastically alter the radiance distribution, e.g., from a near-Dirac delta function in the absence of inelastic processes to a near-isotropic distribution in their presence. The results suggest that in a real ocean, the asymptotic (and near-asymptotic) radiance distribution will tend to become more uniform as the wavelength increases beyond ~500 nm. Finally, it is shown that even for depths far from the asymptotic regime, the radiance distribution of the inelastic component of the light field can be well approximated by the asymptotic theory developed here for inelastic processes. Two exact analytical solutions to the governing equations are also provided.
针对标量近似下的海洋渐近日光场，推导了控制方程，其中包括非弹性过程（拉曼散射和发色溶解有机物荧光）的影响。对控制方程进行了数值求解，并与蒙特卡罗模拟结果进行了比较。结果发现，这些解是蒙特卡罗模拟中渐近场趋近的实际辐射率分布。给出了样本解，以展示光场对介质各种参数的敏感性。对于某些参数值，非弹性过程的包含会极大地改变辐射率分布，例如，从无非弹性过程时的近狄拉克δ函数变为存在非弹性过程时的近各向同性分布。结果表明，在真实海洋中，随着波长增加超过约500nm，渐近（和近渐近）辐射率分布将趋于变得更加均匀。最后表明，即使对于远离渐近区域的深度，光场非弹性分量的辐射率分布也可以很好地用这里为非弹性过程发展的渐近理论来近似。还提供了控制方程的两个精确解析解。
