依据紫外光学系统中紫外反光镜的使用要求,并结合汞灯发光光谱,提出了R＞93%@300~450 nm(R为反射率);Tavg＞85%@500~1 000 nm(Tavg表示平均透过率)的近紫外区宽带高反射率的设计指标。选用Ta2O5和SiO2分别作为高低折射率材料,并采用正交试验法确定了Ta2O5和SiO2膜料的折射率、消光系数和制备工艺参数。在规整周期性膜系的基础上,利用膜系设计软件进行优化设计,同时分析了膜层的敏感度,保证了镀制的可重复性。通过曲线测试和环境试验结果表明,该膜系满足设计使用要求。

According to the operating requirements of ultraviolet reflector in the ultraviolet optical system,and with mercury lamp luminescent spectrum,the near ultraviolet broadband high reflectance design index of R＞93%(300~450 nm) and Tavg＞85%(500~1 000 nm) are presented.The refractive index,extinction coefficient and technological parameters of preparation of Ta2O5 and SiO2 coating materials are determined by orthogonal test,with Ta2O5 and SiO2 as high and low refractive index materials.Based on the regular periodic coating,the coating is optimally designed.Meanwhile,the sensitivity of the film is also analyzed to ensure the repeatability of coating.The results of curve test and environmental test show that the coating meets the design requirements.