本文提出采用三角晶格作为设计 1 550 nm波段光子晶体结构的基础; 在该结构下采用占空比 0.3的结构参数, 可以实现最大禁带宽度; 采用点缺陷和线缺陷相结合, 提出侧耦合结构, 利用基于 FDTD的 Rsoft软件进行仿真计算, 分析了缺陷模、透射谱、稳态时域响应图, 并且计算了光开关的插入损耗、消光比和响应时间等。结果表明：这种结构的光开关插入损耗和消光比等性能都较好, 完全能满足现代应用的要求。

A triangular lattice is proposed as the basis of the 1 550 nm-band photonic crystal structure. We use a duty cycle r/a=0.3 in order to achieve the greatest band gap. Using the combination of point defect and line defect, we propose lateral coupling structure. With the simulation calculation based on the FDTD Rsoft software, the defect mode, transmission spectra and steady-state time domain response are analyzed. At last, the insertion loss, extinction ratio and response time of the optical switch are calculated. The results show that the insertion loss, extinction ratio and other performance of the structure of the optical switch are better, and it can fully meet the requirements of modern applications.