有机聚合物高速电光调制器是全光纤器件，插入损耗低，集成度高，能极大地降低模式失配和调制电压，提高调制效率，是未来超长距离超大容量高速光通信系统中的关键器件之一。将一种基于长周期光纤光栅的光纤聚合物电光调制器看作5层均匀圆光波导，考虑两层电极及其复折射率的实际情况，利用紧致的超格子方法，在复数域分析这种光纤聚合物电光调制器的波导特性。从模式折射率的实部和虚部、模场分布等角度对数值计算结果进行分析表明，只忽略外电极对调制器的波导特性影响很小，考虑电极时长周期光栅的谐振波长比不考虑电极时大，从而影响调制特性。

In the future ultra-span and ultra-capacity optical telecommunication systems, high speed electro-optic polymer modulator is one of the key components, which is an all-fiber component with low insertion loss and high integration. The modulation efficiency can be improved because this kind of modulator can greatly suppress the mode mismatching and operate at much lower modulation voltage. An electro-optic polymer modulator based on the long period grating inscribed in a silica-based optical fiber is modeled as a five-layer uniform circular waveguide, and simulated by using the compact supercell method with the consideration of the complex refractive index of the electrodes. The mode index and mode pattern can be obtained, and can be used to explain some differences of the waveguide properties or the modulator characteristics between with and without the electrodes.