ZnS/MgF_2截止滤光片的潮气吸附

The Moisture Adsorption in Edge Filters Consisted of ZnS and MgF_2

潮气吸附是薄膜光学滤光片的光学不稳定性的主要原因。本文介绍了利用吸附技术研究ZnS和MgF_2构成的截止滤光片、宽带滤光片等的潮气渗透过程及潮气吸附所引起的分光特性的漂移。对于短波通滤光片,这种漂移可达200A左右,而对于间隔层为MgF_2的多腔宽带滤光片.漂移量可达250A左右。这与基于薄膜的聚集密度概念在PC-1500袖珍计算机上模拟的结果相当一致。

It is well known that the moisture adsorption is the main reasonfor optical instability of thin film optical filters. In this paper the study of moisture penetration process in edge filters, multi-cavity broad band pass filtersetc. consisted of ZnS and MgF_2 by using the adsorption technique is presentedand the change in their spectral performance is demonstrated. For short wavepass filters the shift of the edge wavelength is about 200 A, while for multi-cavity broad band pass filters with the spacers of MgF_2 the shift around 250A.These experimental resulfs are well consistent with that of theoretical simulationinvolved the concept of the packing density of thin films, carried out in a PC--1500 computer.