针对三种常见的介质柱横截面分别为正六边形，正方形和圆形的二维光子晶体，提出了一种增大光子带隙的方法.直角坐标系下，使X方向长度增大p倍，并以原点为中心旋转角度φ，通过调整p和φ来降低结构对称性，使用平面波展开法，对其进行了大量的仿真分析.结果表明，结构改变后的光子晶体具有较大的带隙率.对于三种介质柱的三角晶格结构的光子晶体，最大带隙率能达到12％以上，尤其对于正方柱三角晶格光子晶体，最大带隙率达到15.1％.

For three types of conventional 2D photonic crystals with medium column’s cross sections’ shapes of hexagon,square and circular,a method that decreases the length in X direction to be p times and rotates shapes with angle φ for increasing the PBG of the photonic crystals was brought forward.The symmetry of the structures were decreased through changing the values of p and φ.With simulation using planar wave expansion method,the results were show that max PBG rate can reach above 12%,due to the photonic crystals of the three types of medium column with triangular lattice.Especially for photonic crystals of rectangle column with triangular lattice,the max PBG rate arrives at 15.1%.