利用时域有限差分方法，通过数值模拟分别研究了基于光子晶体正负折射原理设计的分束器中介质柱半径和介质柱位置的随机误差对分束器性能的影响，发现当介质柱半径的误差振幅小于0．055倍的介质柱标准半径或者介质柱位置的误差振幅小于0．06倍的光子晶体晶格常数时，正负折射光束的能流透射率均保持在20%以上。

The influences of radius-error and position-error of dielectric-rod on the properties of beam splitter,which is based on positive-negative refraction in photonic crystal,were investigated by numerical simulation with the frequency-difference time-domain method,respectively. It is found that the energy flow transmissivities of positive and negative refractive beams both remained more than 20% when the ratio of the radius-error amplitude and radius is less than 0.055 or the ratio of the position-error amplitude and lattice constant is less than 0.06.