The principle of infrared forehead thermometer to calculate body temperature

Mar 29, 2021

The principle of infrared forehead thermometer to calculate body temperature:


Generally, the infrared wavelength emitted by human body temperature (36℃~37℃) is 9~13 microns. Different temperature measurement locations have different standard temperature ranges, such as:


Anus (36.6℃~38℃)

Oral (35.5℃~37.5℃)

underarm (34.7℃~37.3℃)

cochlea (35.8℃~38℃)

Forehead (35.8℃~37.8℃)


According to this principle, the accurate body temperature can be displayed by correcting the temperature difference between the forehead and the actual body temperature by detecting the surface temperature of the human forehead. Generally, the middle part of the eyes is the radioactive source closest to the normal body temperature for measuring the body surface temperature. It is most suitable to place the forehead gun at a distance of 3-5cm to measure the temperature (usually the thickness of the adult index finger is sufficient, and direct contact is not allowed. Forehead).


Generally speaking, compared with mercury thermometers, the accuracy of forehead thermometers is a bit worse, but it is convenient and easy to use, and it is sufficient for screening.



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