Willers Guido, Hagendorf Christian, Naumann Volker, Holzlöhner Ronald, Guisard Stéphane
Appl Opt. 2022 Apr 1;61(10):2727-2732. doi: 10.1364/AO.452904.
Airborne contaminations on telescope mirrors are an important issue that is significantly affecting their reflectance, IR emissivity, and light scattering properties. Microscopic damage caused by environmental contaminants is of major interest for high-performance telescope mirror coatings. We have exposed unprotected Al coated mirrors under real operation conditions at the Very Large Telescope on Cerro Paranal/Chile for three years. The unique finding is that, in spite of a dry and low-dust environment, the reflective layers are damaged by interaction between dust particles on the Al mirror surface and capillary condensation. We analyze this particular damage mechanism at the microstructural level.
望远镜镜面的空气传播污染物是一个重要问题，严重影响其反射率、红外发射率和光散射特性。环境污染物造成的微观损伤是高性能望远镜镜面涂层的主要关注点。我们将未加保护的铝镀膜镜面在智利帕拉纳尔山甚大望远镜的实际运行条件下暴露了三年。独特的发现是，尽管环境干燥且沙尘少，但铝镜表面的尘埃颗粒与毛细凝聚之间的相互作用会损坏反射层。我们在微观结构层面分析了这种特殊的损伤机制。
