对Bragg光纤中包层制造误差对导模特性的影响进行了深入的分析和研究, 给出了一般N层波导中模式场标量波动方程求解的传输矩阵方法, 并将其应用在Bragg光纤模式场的分析当中。分别研究了Bragg包层存在折射率误差和厚度误差时对光纤基模模式场的有效折射率、模场半径和芯区功率占比的影响, 并利用统计的方法分析了不同制作误差时导模特性的相对变化。折射率误差在1‰的水平时, 基模有效折射率、模场半径和芯区功率占比的方差水平为1.55×10-4、1.04×10-1和1.79×10-2; 厚度误差在2%的水平时模式场参量的方差水平分别为3.61×10-5、1.84×10-2和2.35×10-3。

The impact of fabrication error on mode properties of Bragg fiber is carried out. The transfer matrix method for solving scalar wave equation of the N-layers waveguide is given and applied to guided-mode analysis of the Bragg fiber. The impact of both refractive index error and thickness error on effective index of fundamental mode, mode field radius and power ratio of fiber core are investigated respectively. The dependence of mode properties on fabrication error level is studied in statistical approach. The variances of the effective index of fundamental mode, mode field radius and power ratio of fiber core are 1.55×10-4, 1.04×10-1 and 1.79×10-2 with 1‰ refractive index error, while the variances are 3.61×10-5, 1.84×10-2 and 2.35×10-3 with 2% thickness error.