在普通正六边形光子晶体光纤的基础上,通过改变x轴方向空气孔的大小及分布构造了一种新结构的光子晶体光纤。利用多极法对该光子晶体基模的模场分布及双折射进行了数值计算,分析了光波长与结构参数对双折射的影响,同时对光子晶体光纤的色散特性进行了研究。结果表明,通过改变x轴方向空气孔的大小以及分布结构使光子晶体光纤比普通六边形结构光子晶体光纤的双折射率明显提高,并且具有较低的宽带反常色散,在光纤双折射效应的应用和光学器件的研制等方面具有独特的优势。 Based on the regular hexagonal photonic crystal fiber, a photonic crystal fiber with a new structure was constructed by changing the size and distribution of the air holes in the x-axis direction. The mode field distribution and birefringence of the photonic crystal fundamental mode are numerically calculated by multipole method. The influence of optical wavelength and structure parameters on the birefringence is analyzed. The dispersion characteristics of photonic crystal fiber are also studied. The results show that the birefringence of photonic crystal fiber is significantly higher than that of ordinary hexagonal structured photonic crystal fiber by changing the size and distribution structure of the air holes in the x-axis direction, and has a lower broadband anomalous dispersion. Application and development of optical devices and so has a unique advantage.