Laven Philip
Chemin de l'Avanchet 20, CH-1216 Cointrin, Switzerland.
Appl Opt. 2005 Sep 20;44(27):5675-83. doi: 10.1364/ao.44.005675.
Mie theory can be used to generate full-color simulations of atmospheric glories, but it offers no explanation for the formation of glories. Simulations using the Debye series indicate that glories are caused by rays that have suffered one internal reflection within spherical droplets of water. In 1947, van de Hulst suggested that backscattering (i.e., scattering angle theta = 180 degrees) could be caused by surface waves, which would generate a toroidal wavefront due to spherical symmetry. Furthermore, he postulated that the glory is the interference pattern corresponding to this toroidal wavefront. Although van de Hulst's explanation for the glory has been widely accepted, the author offers a slightly different explanation. Noting that surface waves shed radiation continuously around the droplet (not just at theta = 180 degrees), scattering in a specific direction theta = 180 degrees - delta can be considered as the vector sum of two surface waves: one deflecting the incident light by 180 degrees - delta and the other by 180 degrees + delta. The author suggests that the glory is the result of two-ray interference between these two surface waves. Simple calculations indicate that this model produces more accurate results than van de Hulst's model.
米氏理论可用于生成大气华的全彩模拟，但它并未对华的形成做出解释。使用德拜级数的模拟表明，华是由在球形水滴内经历一次内反射的光线引起的。1947年，范德胡尔斯提出后向散射（即散射角θ = 180度）可能是由表面波引起的，由于球对称性，表面波会产生一个环形波前。此外，他推测华是与这个环形波前对应的干涉图样。尽管范德胡尔斯对华的解释已被广泛接受，但作者给出了一个略有不同的解释。注意到表面波在水滴周围持续地散射辐射（不仅仅是在θ = 180度时），在特定方向θ = 180度 - δ的散射可以被视为两个表面波的矢量和：一个将入射光偏折180度 - δ，另一个将其偏折180度 + δ。作者认为华是这两个表面波之间双射线干涉的结果。简单计算表明，该模型比范德胡尔斯的模型产生更准确的结果。
