用拉盖尔─高斯函数表示梯度型单模光纤的特性参数

Characterization of Single-Mode Graded-Index Fibers by Expanding Model Fields in Laguerre-Gaussian Functions

本文用拉盖尔－高斯函数来表示梯度单模光纤的特性参数。恰当应用拉盖尔多项式的性质和汉格尔交换理论，光纤参数如远场分布，模斑尺寸等可以有解析式计算，结果十分简单且物理意义明确。文中给出了数值计算结果并与准确值进行了比较，最后讨论了本文方法的优点．

In this paper, characterization of single-mode graded-index fibers by expanding modal fields in Laguerre-Gaussian functions has been presented. Applying properties of Laguerre polynomials suitably and Hankel transform theory, fiber parameters, such as far field, spot size etc, have been calculated analytically. The final expressions are very simple and without loss of physics insight of view. Numerical examples are given and compared with the exact results. Merits of using this method have been discussed, too.