The two-color thermometer is relative to the single-color thermometer, and it is also a unique type. The working principle of the two-color thermometer is: the ratio of the radiation energy of two different bands has a certain corresponding relationship with the temperature. Two sets of narrow-band monochromatic filters are used to receive the radiant energy of two adjacent bands, convert them into electrical signals, and compare them. The temperature of the measured object can be determined by this ratio.

We analyze that the two-color temperature measurement technology is more stable and accurate than the single-color temperature measurement technology. Since it determines the temperature by the ratio of radiant energy in two different bands, it reduces the dependence on the radiant energy value and is more suitable for harsh measurement environments than monochromatic thermometers. For example, when the target is occluded, or when measuring smaller targets, the two-color pyrometer is more advantageous.
When the target does not fill the field of view of the thermometer, when measuring a smaller target and the target cannot fill the field of view, or when measuring a moving target, the radiated energy will also decrease, which has a certain impact on the single color* As long as the background temperature is lower than the measured target temperature, accurate measurement results can be obtained. This is a clear result of the comparison of the advantages of a two-color thermometer over a single-color thermometer.
There is also a dual-color thermometer when the target emissivity is low or changing, when the measured target emissivity is unknown, or when the target emissivity changes, as long as the emissivity changes in the two bands are caused by the same factor, Then it is more accurate to measure with a two-color thermometer than a single-color thermometer.
Two-color thermometers and single-color thermometers have the characteristics of reliability and fast response, and are widely used in non-ferrous smelting, powder metallurgy, medium and high frequency induction heating, casting, ceramics, welding and heat treatment. Various industries and online temperature in harsh environments It can also be used in other fields such as scientific research and medical treatment.