Lock J A, Adler C L, Hovenac E A
Department of Physics, Cleveland State University, Ohio 44115, USA.
J Opt Soc Am A Opt Image Sci Vis. 2000 Oct;17(10):1846-56. doi: 10.1364/josaa.17.001846.
We use the semiclassical limit of electromagnetic wave scattering theory to determine the properties of the exterior caustics of a diagonally incident plane wave scattered by an infinitely long homogeneous dielectric circular cylinder in both the near zone and the far zone. The transmission caustic has an exterior/interior cusp transition as the tilt angle of the incident beam is increased, and each of the rainbow caustics has a farzone rainbow/exterior cusp transition and an exterior/interior cusp transition as the incident beam tilt angle is increased. We experimentally observe and analyze both transitions of the first-order rainbow. We also compare the predictions of the semiclassical approximation with those of ray theory and exact electromagnetic wave scattering theory.
我们利用电磁波散射理论的半经典极限来确定在近区和远区中，无限长均匀介质圆柱对斜入射平面波散射的外焦散特性。随着入射光束倾斜角的增加，透射焦散会发生外/内尖点转变，并且每个彩虹焦散在入射光束倾斜角增加时，会发生远区彩虹/外尖点转变以及外/内尖点转变。我们通过实验观察并分析了一阶彩虹的这两种转变。我们还将半经典近似的预测结果与射线理论和精确电磁波散射理论的预测结果进行了比较。
