High-performance infrared narrow-bandpass filters for the Indian National Satellite System meteorological instrument (INSAT-3D).

This paper describes the design and manufacture of a set of precision cooled (210 K) narrow-bandpass filters for the infrared imager and sounder on the Indian Space Research Organisation (ISRO) INSAT-3D meteorological satellite. We discuss the basis for the choice of multilayer coating designs and materials for 21 differing filter channels, together with their temperature-dependence, thin film deposition technologies, substrate metrology, and environmental durability performance.