Radiation Heat Transfer in Imaging Infrared SpectrometerA. Jhaveri , M. Kushhare , A. Bhargav ,
 Indian Institute of Technology Gandhinagar, Gandhinagar, Gujarat, India.
Imaging Infrared Spectrometer (IIRS) is a Hyperspectral optical imaging instrument which measures the spectra of a scene in high resolution within spectral bands covering Near Infrared (NIR) to Mid Infrared (MIR) regions. Radiation entering the spectrometer assembly governs the temperature of different internal parts and hence plays an important role in determining the desired spectral resolution of the scene. Here an effort has been made to closely speculate the temperatures and heat fluxes inside the spectrometer assembly and understand their inter-dependency using COMSOL Multiphysics® software. Geometrical Ray Optics coupled with Heat Transfer physics has been used to simulate the system assembly operating at cryogenic temperatures. The current simulation investigates the variation of dependent parameters for source power of 1000 mW.