在本論中我們提出一種數值分析法，用以計算光波導(optical waveguides)的模態光場(modal optical field)。一般人通常以變分分析法(variational analysis)算出各項模態參數，而吾人則提出一種可解出相同結果的疊代演算法。本論文即以薺杜式鈦擴散波導(Ti-diffused ridge waveguides)為研究主題，將演算的過程及結果討論如下。
We propose a numerical method to compute modal fields of optical waveguides in this paper. Instead of traditional variational analysis, an iteration method is used to solve the same problems. And a Ti-diffused ridge waveguide is selected as a topics of research. The simulation processes and results are described as follows.
