利用有限差分法，研究了一种在包层小孔中填充可变折射率材料的新型光子晶体光纤的传输特性，并讨论了其在传感器设计方面的应用前景。分别模拟了包层孔为单圈、两圈、三圈结构下的光纤传输谱，在两圈孔的情况下，找到了合适的工作波长区间，并发现该工作区间的位置对于填充材料的折射率表现得很敏感，且呈近似线性关系。该折射率在1．48～1．8区间内每变化0．01，导波区间位置平均移动24nm。结论表明，与传统的光波导折射率传感器相比，这种新型光子晶体光纤折射率传感器具有测量范围较大，灵敏度较高的优点。

By finite difference method,the spectrum of photonic crystal fibers with high-index inclusions is obtained and its application for sensor designing is discussed. The simulation of transmission spectrum of this fiber with different rings of cladding holes is carried out. In the case of two rings of holes,a suitable passband is found and its stop wavelength changes with high sensibility,almost linearly,as the index of inclusions changes. In average,the wavelength changes 24 nm when the index changes 0.01 in range of 1.48～1.8.This conclusion implies that the novel photonic crystal fiber sensor has high sensitivity and wide measuring range.