一种精确测量波导参数的方法──M线光谱法

A Preeisive Method for Measurement of the Waveguide Parameters──M Line Spectroocopy

本文根据棱镜耦合器内的全反射原理，利用Ｍ线光谱法精确地测量了质子交换ＬＴ波导的衬底和波导模式的有效折射率，借助于ＩＷＫＢ法计算出了波导的折射率的分布，并采用Ｆｅｒｍｉ公式拟合得到波导的表面折射率，其测量精度可达１０￣（－４）量级。

In this paper the refractive index of the proton-exchanged LT waveguide and the substrateare measured in a high precision by M line spectral method in the principle of the totalinternal reflection in the prism coupler. The distribution of the refractive index in waveguideis calculated by IWKB methed ,and the surface refractive index of the waveguide is fittedaccording to Fermi formula with the precision as high as 10￣(-4).