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The use of thermovision systems for the remote sensing of surface temperatures has been conventional for a long time. In recent years serious progress has been achieved in the reduction of instrumental errors of IR receivers and increase of quality of thermal images visualization and registration. The smaller progress is observed in questions of reduction of methodical measuring errors, in a sense of the determination by thermovision methods of the true (thermodynamic) temperature of a radiating surface, its factor of radiation, and the determination of a ratio of own and reflected radiation. It is expected that the essential progress can be achieved by creation of thermovision systems, carrying out registration of objects in several spectral subranges of ranges 3-5 or 8-14 micrometer. A similar result can be achieved by use of single-channel devices with a set of spectral filters. Such an approach provides, in essence, the registration of multispectral thermal images, further mathematical processing of which (or processing in a real time scale), permits us to make approaches to solving the above mentioned problems. Thus, the problem of determination of a spectrum of radiation for each point of the image on the basis of results of multispectral measurements becomes the central one. As a criterion the most optimum accuracy and complete time of measurement (for single-channel systems) or amount of channels (for multichannel systems) should be used. Naturally, the term 'accuracy' must be determined. The offered technique was being created during scientific cooperation between the Institute of Radio-electronics of the Russian Academy of Sciences (IRE RAN), producing thermovision systems, and the State Research Institute of Aviation Systems (GosNIIAS) which makes software for such devices and realizes the multispectral processing.
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