Automatic compensation of emissivity in three-wavelength pyrometers

The paper presents a method of temperature measurement with automatic compensation of emissivity affecting a measurement result. For temperature calculation, the data from three independent channels are taken and an object’s emissivity is approximated with constant, power, and exponential functions. One of these functions is selected automatically and such a selection is made on the basis of mutual relations between luminance temperatures and temperatures resulting from a ratio of signals for two measuring wavelengths. A chosen approximating function indicates a choice of temperature calculation method.