通过改变介质柱之间的距离、介质柱半径以及介质柱的介电常数构造了3种二维渐变的光子晶体，应用时域有限差分(FDTD)法计算了透射谱，并分别对不同形式渐变组合的光子晶体结构进行了比较分析。仿真结果表明，不同形式的渐变组合对光子晶体禁带有着不同的影响，可以获得比一维渐变型光子晶体更大的禁带宽度。

This paper designs three kinds of graded photonic crystal structures by changing the gaps between dielectric columns, radius of dielectric columns and dielectric constant, calculates the transmission spectrum by using the Finite Difference Time Domain (FDTD) method and compares and analyzes photonic crystal structures with different forms of graded combinations. Simulation results show that different combinations have different effects on photonic bandgap and can obtain still larger bandgap width than one-dimensional photonic crystals.