讨论了一种用于DWDM系统中的光开关、偏振无关隔离器等单元器件中的微小薄膜型偏振分束器制造的关键技术。光学膜层采用数学多重优化设计方法；采用Monte Carlo允差分析原理分析膜层的容差，以便选择更易制备的膜系；计算膜层的Macleod极值灵敏度，得到所选膜系各个膜层的误差要求；模拟光学监控过程，以制定相应的膜厚监控策略。设计了实用的棱镜胶合装置，得到了较高技术指标的PBS棱镜。结果表明，棱镜的光学冷加工，是器件制造的基础；光学薄膜的设计与制备是器件制造的关键，也是难点；棱镜的胶合是器件不可忽视的环节。

The key technology to make a micro polarized beam splitter(PBS)used as optical switcher and polarization-free isolator in the DWDM system is discussed. The optical film is designed with optimum method. The tolerance of the layer is modeled through Monte Carlo method in order to obtain simple manufacture process. The film thickness error of the each layer is obtained by calculating the Macleod maximum sensitivity. The film thickness is controlled by modeling the optical monitoring processes. A practical cemented prism is designed,and a PBS prism with advanced technique parameters is obtained. The results show that the optical cold machining for the prism is the base to make the PBS,the key issue and difficulty are optical film design and coating,and it is also important to cement the prism.