What are the causes of errors in temperature measurement by infrared thermometers?
Non-contact infrared radiation thermometers are divided into industrial and medical types. To measure human body temperature, medical infrared thermometers, infrared ear thermometers, and infrared body surface temperature detectors should be used because they have narrow measurement ranges, high resolution, and small errors. . In contrast, industrial infrared thermometers have a wide measurement range, low resolution, and large errors. However, many anti-SARS checkpoints still use industrial infrared thermometers to measure human body temperature. Therefore, it can only serve as a preliminary screening, and medical thermometers must be used to identify and exclude suspected fever subjects.
Nowadays, many thermometers have the problem of large errors. According to relevant personnel, various existing infrared thermometers are modified from industrial thermometers and can only measure the surface temperature of the forehead, not the temperature of the armpits. The forehead surface temperature is not only lower than the armpit temperature, but is also greatly affected by the ambient temperature, causing large measurement errors in various existing infrared thermometers. Infrared temperature measurement products with ambient temperature compensation function should be developed, which can accurately calculate the armpit temperature based on the human forehead temperature and ambient temperature.
According to relevant experts, in order to put social interests first and gather more resources and strength to fight against SARS, the new infrared thermometer can significantly reduce the technical and manufacturing threshold of infrared temperature measurement equipment, and also solve the problem of domestic infrared thermometers. The core components of temperature measurement are completely dependent on imports, resulting in shortage of supply and high prices.
So, what is the technological content of the current infrared thermometer? Experts from the China Institute of Metrology said in an interview with reporters that first of all, the measurement accuracy of the thermometer is related to the accuracy of the instrument itself and the quality of the instrument itself; Secondly, the difference in measurement standards between the calibration temperature of the measuring instrument in the laboratory and the actual measured temperature can also easily cause measurement errors; thirdly, thermometers now measure the forehead, palms, face and other parts of the human body, and the measurement results It belongs to a person's body surface temperature, and the body surface temperature may fluctuate due to the influence of a person's activity status, so it may not truly represent the human body temperature.
Experts also revealed that a measurement standard for temperature measuring instruments is currently being revised. The measurement standard will stipulate the maximum measurement error of the instrument and other factors. At the same time, scientific and technical personnel of the China Institute of Metrology are working overtime to produce the infrared thermometer calibration device recently developed by the institute. They plan to equip 50 ports with this device. This device not only fills the gap in my country's demand for infrared radiation thermometers. The field calibration device is blank, and the infrared radiation thermometer has a crosshair.
