Design and technical demonstration of a spectral dispersive module for an IR hyperspectral instrument for Earth monitoring from geo-synchronous Earth orbit

This paper presents the development of an instrumental prototype for IR hyperspectral imaging from geo-synchronous earth orbit (GEO). Within the framework of collaboration and funding support from the Canadian Space Agency (CSA), Telops performed the development and technical demonstration of a spectral dispersive module (SDM) with potential application for the US NOAA Hyperspectral Environmental Suite (HES). HES development will provide infrared and visible environmental data collection capabilities for the next GOES program series of geo-synchronous satellites that will collect weather and environmental data to aid in the prediction of weather and in climate monitoring. The design of the SDM is based on an Offner configuration. Such a design allows the gathering of high spatial and spectral resolution data while keeping the spatial and spectral distortions smaller than the size of a pixel. A convex diffraction grating is used in the system as a spectrally dispersing element. The targeted application of this Offner spectrometer configuration is weather sounding in the mid-IR spectral range. The design and demonstration phase of the SDM is described. Test results, such as spectral/spatial resolution, distortion, transmission and efficiency, with the engineering laboratory model are presented.