给出了 Ti 扩散 LiNbO_3条波导任意阶导模场分布的近似解,通过逐点近似法确定待定常数,分析了它的物理意义,也给出了导模的传播常数和有效折射率的解析式,与变分法相比,这种方法物理概念明确,计算量小,寻优简单,为集成光学的设计提供了一种计算精度较高的计算方法. The approximate solution of arbitrary order mode field distribution of Ti diffused LiNbO 3 waveguides is given. The undetermined constant is determined by the point-by-point approximation method. Its physical meaning is also analyzed. The propagation constants and effective refractive indices of guided waveguides are given. Compared with the variational method, this method has a clear physical concept, a small amount of calculation, and a simple optimization, which provides a computationally accurate calculation method for integrated optical design.