Filters for the v2 band of CO2 : monitoring and control of layer deposition
C S Evans, R Hunneman, J S Seeley
Applied Optics, Vol 15, No 11, Pages 2736-2745 (1976)
Two types of multilayer interference filter are required for temperature sounding the earth's atmosphere. In relation to the 668 cm-1 v2 band of CO2 these are narrowband (4 cm-1 wide for the Q branch, 10 cm-1 for the R branch) or isolation (60 cm-1 wide for the complete centre of the band). Difficulty in manufacturing the filters for NIMBUS-SCR and -PMR spaceflight has indicated a need for improvement in the monitoring and control of the deposition of layers, and the paper describes a realization of this. The consequent effect on filter performance (utilizing a particular combination of layer materials) is described.