Thermal infrared spectroscopy

Thermal infrared spectroscopy (TIR spectroscopy) is the subset of infrared spectroscopy that deals with radiation emitted in the infrared part of the electromagnetic spectrum. The emitted infrared radiation, though similar to blackbody radiation, is different in that the radiation is banded at characteristic vibrations in the material. The method measures the thermal infrared radiation emitted (as opposed to being transmitted or reflected) from a volume or surface. This method is commonly used to identify the composition of surface by analyzing its spectrum and comparing it to previously measured materials. It is particularly suited to airborne and spaceborne applications.

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