红外探测装置中光谱分光镜的设计与制备

Design and fabrication of beam splitters in infrared detection device

在红外探测装置中,光谱分光镜是用来把3μm^5μm和8μm^12μm 2个波段的光谱分开的零件。介绍了一种在通用镀膜机上制备光谱分光镜的新工艺。在该膜系的设计过程中,把Willey公式引入到对其平均透过率最高值进行估算的过程中,同时针对国产镀膜机控制精度不高的特点,尽量使用规整膜层进行设计。为了进一步提高8μm^12μm波段的透过率,在膜系的最外侧引进了一层自行配制的低折射率氟化物材料,制备出了符合技术指标的红外光谱分光镜。

Beam splitters for infrared spectrum are used to split the band of 3 μm to 5 μm and 8 μm to 12 μm in infrared detection devices. A new method of designing and fabricating infrared beam splitters with a conventional coater is introduced. In the course of design, we estimated the highest value of average transmission with the formula of Willey, which was used in the design of the beam splitters. Considering the low precision of the available coater, we attempted to design coating with quarter-films. For improving transmission from 8μm to 12 μm, a selfprepared low refractive index material was deposited on the coating. The beam splitters for infrared spectrum fabricated met the required technical specifications.