What is a radiation thermometer?

All objects radiate some thermal energy from their surfaces. A radiation thermometer measures the temperature of an object by measuring the amount (intensity or brightness) of its thermal energy in a non-contact manner and converting it into temperature.

Therefore, the radiation thermometer is sometimes expressed as a non-contact thermometer. Incidentally, this energy becomes longer wavelength as the temperature is lower. Normally, 0.75 to 2.5μm is called near-infrared, 2 to 25μm is called mid-infrared, and 2μm to 1mm is called far-infrared.

The radiation thermometer generally uses the 0.7 to 14μm wavelength band, so it is also called an infrared thermometer.