Hi everyone, I have a problem a bit tricky to solve which deals with Infrared absorbers. In my setup experiment, some IR radiations are emitted, let's say black body radiations at 300K, so IR wavelengths centered on 10,6µm. I want to absorb them (entirely) by a surface (at about 77K) made of several layers to prevent my system from any heating. Consequently, I also want to prevent from IR reflection on this surface. Maybe some of you can help me to "build" this surface. For the moment, I have been thinking about a surface made of : (from outer to inner layer) - layer 1 : Diamond (Good IR transmission 70% (10µm), quite low reflection 15%). It has to be diamond, it cannot be changed. - layer 2 : Silicon or Zinc Selenide (To absorb/reflect emission from absorber (layer3)) - layer 3 : Fused Silica (To absorb the main IR radiations : Huge absorption band and IR range between 5 to 80µm). However some annoying things are the 2 peaks of reflection at 9 and 21µm ... Layers has to be thick as possible... If anyone of you have some ideas or advise regarding as materials (SiO, Black Silicon ...) I did not mention or did not think about, please tell me, I will be glad to know :) Thanks in advance Have a nice day.