为了研究纤芯-包层交界处石英环厚度对空芯光子带隙光纤的传输带宽、色散、纤芯能量、非线性系数的影响，利用全矢量有限元法对所设计的7孔空芯光子带隙光纤进行仿真，得到了纤芯半径固定时，不同石英环相对厚度情况下，光纤带宽、色散、纤芯能量及非线性系数随波长的变化曲线。结果表明，石英环相对厚度的最佳取值范围为0.5～0.6，这为光纤设计提供了理论依据。

In order to study effect of the silica ring at the core-cladding interface on the transmission bandwidth, dispersion, core-confined energy and nonlinear coefficient, for the designed 7-cell hollow-core photonic bandgap fibers(HC-PBGFs), they were numerically simulated by means of full-vector finite element method, and the curves of the transmission bandwidth, dispersion, core-confined energy, nonlinear coefficient in different normalized thickness of the silica ring with the same core radius were obtained. The simulation results show that the best range of normalized thickness of silica ring is 0.5 to 0.6, which provides theoretical evidence to design the HC-PBGFs.