中波红外短波通滤光片的设计与镀制技术研究

研究了中波红外宽光谱短波通滤光片优化设计和镀制,论述了设计该种滤光片的原则和方法。根据等效折射率理论,以周期性对称膜系为基础,使用部分膜层优化方法,设计了中波红外宽光谱短波通滤光片,在2 300～4 700 nm透射波段范围上的平均透射率设计值大于90%,在5 000～6 300 nm截止波段范围上的平均透射率小于1.00%。采用"会聚光红外光学系统"和等离子体辅助沉积工艺实验制备了滤光片。实验表明,在透射波段范围上的平均透射率约为83%,截止波段的平均透射率约为0.45%。结果表明,部分膜层优化方法设计的膜系,膜层结构简单,有利于膜层厚度的监控。

DESIGN AND PREPARATION OF MEDIUM-WAVE INFRARED SHORT-WAVELENGTH PASS FILTER

In this paper, optimization design and preparation of the medium-wave infrared broad-band short-wavelength pass filter was investigated, and design principles and methods was discussed. The equivalent-index method was used to design the falter and thicknesses of some chosen films were optimized. The short-wavelength pass filter in medium-wave infrared band was designed, which shows an average transmittance ratio is more than 90% at wavelength region 2300- 4700mm and an average transmittance ratio is less than 1.00% at 5000~6300nm. The filter was prepared successfully by using a convergent infrared optical system and a plasma assistant deposition technology. The result shows that make use of the method of optimizing some chosen filma, the film system is simplified and it is convenient to monitor the filmm thickness.