短中波红外探测系统宽波段高透过率薄膜

Short-medium infrared detection system broadband high transmittance film

短中波红外探测系统能够同时响应短波红外及中波红外两个波段,可以满足复杂探测环境的使用要求,在军用及民用方面获得了广泛应用。为提高红外探测器的精度,缩短响应时间,需要研制满足系统要求的宽波段高透过率薄膜。结合Baumesiter减反射膜设计理论,对变尺度算法的评价函数进行了优化,建立了新型加权评价函数模型,在2.6~3.3μm的水吸收波段,根据模型设计了低敏感度高容差的膜系结构。并针对水吸收波段优化制备技术,研究了不同离子源辅助沉积参数对MgF2光谱特性的影响,同时采用阶梯性退火工艺,得到了一种有效降低水吸收的方法。最终所制备的薄膜在1.5~5μm波段范围内光谱透过率大于96.5%。

Short-medium wave infrared detectors can work both in the low light night vision band and medium band at the same time, which can meet the requirement of complex detection environment.Infrared detector are widely used in military and civil fields. In order to improve the precision of infrared detector and shorten the response time, it is necessary to develop a wide band film with high transmittance that meets the system requirements in the short-medium band. The evaluation function of the variable scale algorithm was optimized based on the Baumesiter anti-reflection membrane design theory. A new weighted evaluation function model was established to design the membrane system structure with low sensitivity and high tolerance in the water absorption band of 2.6-3.3 μm. The influence of different ion source assisted deposition parameters on the spectral characteristics of MgF2 was studied by optimizing the preparation technology for the water absorption band. Meanwhile,a step annealing process was used to obtain an effective method to reduce the water absorption. Finally,the spectral transmittance of the prepared film was greater than 96.5%.