用时域有限元差分的子域合成法(Synthetic subdomain method of FDTD)对大规模的光波导模拟, 把仿真的光波导划分成两个或多个区域, 在不影响仿真精度的条件下, 删除对仿真对象影响不大的区域, 并相应改变吸收边界条件进行时域有限元差分法数值模拟, 考查光的传播和损耗状况, 并与常规方法的运算结果相比较, 结果一致且不影响计算精度。与常规方法相比, 两段子域合成法所占内存约为前者的55％, 时间约为前者的60％, 三段子域合成法所占内存约为前者的31％, 时间约为前者的28％, 可见子域合成法比常规方法更有利于应用于大规模集成光波导的数值模拟仿真, 对节省硬件及时间资源具有实际意义, 提高工作效率。

The synthetic subdomain method (SSDM) of finite-difference time-domain (FDTD) method is used to simulate the large-scale optical waveguides. The waveguide is divided into two or more parts, and the parts whose influence on the simulation result is ignorable are deleted on the condition that the simulating precision does not deteriorate. In the simulation, the absorption boundary condition is changed accordingly, and the light transmission and loss are also considered. The simulation results agrees with that of conventional method, and no precision decline is found. The two-part method occupies 55% memory and 60% time of the conventional FDTD method. Three-part SSDM uses 31% memory and 28%. It is demonstrated that the SSDM is superior to the conventional FDTD method for large-scale integrated optical waveguide simulation, saves hardware resource and time, and improves the working efficiency.