Seshadri S R
J Opt Soc Am A Opt Image Sci Vis. 2003 Sep;20(9):1818-26. doi: 10.1364/josaa.20.001818.
Electromagnetic beams in a uniaxial crystal are treated with emphasis on the extraordinary mode. A virtual source that generates a basic elliptical Gaussian wave propagating obliquely to the optic axis is identified. An exact expression is obtained for this basic elliptical Gaussian wave that simplifies to the corresponding basic elliptical Gaussian beam in the appropriate limit. In the direction of amplitude propagation, the paraxial result becomes identical to the exact result and the sum of all the nonparaxial contributions vanish. The characteristics of the basic elliptical Gaussian beam are illustrated with a numerical example. From the spectral representation of the basic Gaussian wave, the first three orders of nonparaxial corrections for the basic elliptical Gaussian beam are determined. The nonparaxial results reduce correctly to those of the fundamental Gaussian beam in an isotropic medium.
对单轴晶体中的电磁束进行了处理，重点关注异常模式。确定了一个虚拟源，该虚拟源产生一个基本椭圆高斯波，该波倾斜于光轴传播。得到了这个基本椭圆高斯波的精确表达式，在适当的极限情况下，该表达式简化为相应的基本椭圆高斯光束。在振幅传播方向上，傍轴结果与精确结果相同，所有非傍轴贡献的总和为零。通过一个数值例子说明了基本椭圆高斯光束的特性。从基本高斯波的频谱表示中，确定了基本椭圆高斯光束的前三阶非傍轴修正。在各向同性介质中，非傍轴结果正确地简化为基本高斯光束的结果。
