为了能同时满足半导体激光器和YAG激光器对薄膜的特殊要求,在分析高反射膜理论的基础上,选取TiO2和SiO2为高、低折射率材料镀制了周期性多层介质高反射膜。研究了材料的光学及机械特性,重点解决了薄膜的消偏振和抗激光损伤问题。实验采用电子束真空镀膜并加以考夫曼离子源辅助沉积,利用TFC软件进行膜系设计,通过调整镀膜工艺参数和监控方法,在10 mm1.8 mm的K9基底上镀制了符合要求的高反射膜,结果表明,当激光以45入射时,薄膜在900~1 100 nm的p光与s光的反射率均大于99.95%。所制备的高反射膜性能稳定,抗激光损伤阈值高,能同时满足两种激光器的使用要求。
In order to meet the special requirements of semiconductor lasers and YAG lasers for films synchronously, the principles of a high reflectance film were researched. Then, by choosing the TiO2 and SiO2 films as the higher and lower reflectance materials, a high laser-induced damage threshold reflectance film was deposited. The optical and mechanical properties of the materials were investigated and the depolarization and anti-laser-induced damage of the film were overcome. In experiments, the electron beam vacuum coating and the Kaufman ion source assisted technique were used to deposit the film and the TFC software was used to design the thin-film structure. By adjusting the parameters of coating process and monitor method, the high reflectance film was successfully deposited on a 10 mm1.8 mm K9 substrate. Obtained results show that the both reflectances of p-component and s-component have exceeded 99.95% at the wavelength of 900 nm~1 100 nm when the incidence of laser is 45. The experiments demonstrate that the high reflectance film has a stable property and a high laser-induced damage threshold, and it is suitable for both semiconductor lasers and YAG lasers.