本文介绍了一种在半导体光放大器镀膜过程中监测端面反射率的简单而有效的方法。理论模型的建立考虑了光放大器的漏电流和自发发射速率随载流于浓度的非线性变化，并且基于实验测量的ＰＩ（输出功率与注入电流）曲线，采用曲线拟合的方法来修正一些依赖于器件的参数，理论计算结果与有关文献的测量结果较好地吻合。 This article presents a simple and effective way to monitor the reflectance of the facets during the coating of semiconductor optical amplifiers. The theoretical model was established considering the nonlinear changes of leakage current and spontaneous emission rate of the optical amplifier with the concentration of carrier current. Based on the experimentally measured PI (output power and injection current) curves, a curve fitting method was used to correct some dependencies The parameters of the device, the theoretical calculation results and the relevant literature measurement results fit well.