In nature, all objects with temperatures above absolute zero are constantly emitting infrared radiation energy to the surrounding space. The magnitude of the infrared radiation energy of an object and its distribution by wavelength are closely related to its surface temperature. Therefore, by measuring the infrared energy radiated by the object itself, it can accurately measure its surface temperature, which is the objective basis on which infrared radiation is measured.
The infrared thermometer consists of an optical system, a photodetector, a signal amplifier, signal processing, and display output. The optical system converges the target infrared radiation energy within its field of view. The size of the field of view is determined by the optical components of the thermometer and their position. The infrared energy is focused on the photodetector and converted into a corresponding electrical signal. Infrared Thermometer Principle The black body is an idealized radiator that absorbs the radiant energy of all wavelengths. Without the reflection and transmission of energy, the surface emissivity is 1. The signal passes through the amplifier and the signal processing circuit, and is converted to the temperature value of the measured object after being corrected according to the algorithm of the internal treatment of the instrument and the target emissivity.
When using the infrared radiation thermometer to measure the temperature of the target, first measure the amount of infrared radiation in the range of the target, and then calculate the temperature of the target by the thermometer. The monochromatic thermometer is proportional to the amount of radiation in the band; the two-color thermometer is proportional to the ratio of the amount of radiation in the two bands.