基于液晶的电场调控特性，利用时域有限差分（FDTD）法和完美吸收边界条件（PML）数值计算了：三角格子周期性排列的圆空气孔构成的完美二维光子晶体的禁带结构；纤芯填充5CB液晶光子晶体光纤在外加电场方向与x轴夹角θ分别为0°, 30°, 60°, 90°时的波谱图；以波长2504 nm和θ分别为0°, 30°, 60°, 90°对应的局域模波长作为波源时的光场分布。结果表明：完美二维光子晶体存在范围为2334~2438 nm的禁带；纤芯填充5CB液晶光子晶体光纤的局域模波长随着夹角θ的增大向短波方向移动，当夹角θ在（0°，90°）范围内变化时，局域模波长的最大调控量为73 nm；对于波源为禁带范围外的光波，光场能量不局限在光纤纤芯；对于光源为局域模波长的光波，夹角θ越大，光场能量越集中于纤芯区，且光场能量分布越均匀。

Based on the electrically control characteristics of liquid crystal, the band-gap of an perfect two-dimensional photonic crystal which is composed of triangular lattice circular air holes, the spectrum of liquid crystal 5CB filled photonic crystal fiber for different angles θ which are between the direction of external electric field and x-axis, and the optical field distributions when the wave source wavelength is 2504 nm and different defect modes wavelength are numerically calculated by finite-difference time-domain (FDTD) and perfectly matched layer (PML). The results show as follow: the band-gap of an perfect two-dimensional photonic crystal ranges from 2335 nm to 2438 nm; the defect modes move to short-wave with the increasing of the angle θ, and the maximum value of regulation is 73 nm when the angle θ ranges from 0° to 90°; the light energy will not localize at the fiber core when the wave source wavelength is not within the band-gap limits; the light energy will localize at the fiber core when the wave source wavelength corresponds to different defect modes wavelength, and its distribution is more homogeneous with the increment of the angle θ.