为解决二维光子晶体在光束调整和光束偏转中的应用，采用有限时域差分法和完全匹配层吸收边界条件，通过在结构中引入消反层，从理论上实现基于二维光子晶体的偏振分束器。优化计算表明，通过随光频的改变调节消反层参数，可以实现TE模超过95%的光发生透射，TM模超过95%的光发生反射，从而使TM模与TE模分离。引入消反层的偏振分束器具有尺寸小、透射率高、分束角大和偏振分束率高等优点，在高密度集成光通信系统中有广泛的应用。

For the applications of 2-D photonic crystals in optical beam adjustment and deflection, a 2-D photonic crystal-based Polarization Beam Splitter (PBS) is theoretically realized by adopting the FDTD method and perfect matched layer absorbing boundary conditions and introducing an anti-reflection layer in the structure. Optimization calculations show that by adjusting the anti-reflection parameters with the changes of the optical frequency, over 95% of light energy in the TE mode is transmitted and over 95% of light energy in the TM mode is reflected, thus separating the TM mode from the TE mode. Small in size, high in transmittance, large in splitting angle and high in polarization splitting rate, the PBS introduced in the anti-reflection layer is extensively applied in high-density integrated optical communication systems.