长波红外减反射膜及锥镜膜厚均匀性研究

Study on thickness uniformity of long wave infraredantireflection film and conical mirror

红外探测因全天候、作用距离远和抗干扰性好等优点而被广泛应用。本文提出在锥镜上制备8~12μm反射率小于0.5%的长波红外减反射膜,利用Essential Macleod软件,在ZnS基片上完成了长波红外减反射膜的膜系设计。采用物理气相沉积方法,选择n=4.3@10μm的Ge做基片和镀膜材料的粘结层,n=2.2@10μm的ZnS为高折射率材料,n=1.35@10μm的YF_(3)为低折射率材料,完成了光学薄膜的制备。提出锥镜膜厚均匀性的补偿方法,通过使用修正后的补偿挡板,使10°锥镜薄膜厚度均匀性达到99%。利用Lamda1050光谱仪测试了锥镜的反射光谱曲线和薄膜厚度均匀性测试曲线,结果表明所研制的膜层在8~12μm处反射率均值为1.483%,对试验件开展了环境适应性测试,测试结果满足使用要求。

Infrared detection is widely used because of its advantages of all-weather,long range and good anti-interference.In this paper,the preparation of long-wave infrared antireflection film with reflectivity less than 0.5%at 8~12μm on cone mirrors is proposed,and the design of film systems for long-wave infrared antireflection film on ZnS substrate using Essential MacLeod software is achieved.Using the physical vapor deposition method,n=4.3@10μm Ge is selected as the bonding layer between the substrate and coating material,n=2.2@10μm ZnS as a high refractive index material,and n=1.35@10μm YF_(3)as the low refractive index material to complete the preparation of optical thin film.A compensation method for the film thickness uniformity of cone mirror is proposed.By using the modified compensation baffle,the film thickness uniformity of 10°cone mirror can reach 99%.The reflection spectrum curve and film thickness uniformity test curve of the cone mirror are measured by Lamda 1050 spectrometer,and the results show that the developed film layer has an average reflectivity of 1.483%at 8~12μm and the environmental adaptability test is carried out on the test pieces,and the test results meet the application requirements.