High-performance infrared narrow-bandpass filters for the Indian National Satellite System meteorological instrument (INSAT-3D)
G J Hawkins, R E Sherwood, B M Barrett, M Wallace, H J B Orr, K Matthews, S Bisht
Applied Optics, Vol. 47, No. 14 (2008)
This paper describes the design and manufacture of a set of precision cooled (210K) 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.