Is the infrared thermometer accurate? An infrared thermometer is a kind of thermometer that uses the principle of infrared to measure body temperature. The components of the infrared thermometer are mainly electronic accessories, so the accuracy of the infrared thermometer measurement depends on the electronic accessories used. Infrared clinical thermometers are electronic instruments, so certain errors will occur when they are used, but the results will not show too much deviation, will not affect the measurement results, and are generally very accurate.

This passage is going to talk about the followings of the accuracy of infrared thermometer box: 

Measurable temperature range

Specifications of infrared thermometer

Professional explanation

Measurable temperature range

"Temperature gun" is a kind of infrared thermometer. When using, just aim the "muzzle" at the object to be measured, and the display screen of the "tail" can directly report the temperature of that object with numbers. This wonderful "pistol" can measure the temperature range of 20~1600 degrees Celsius. . When a person walks near it, the measurement result is automatically converted into oral temperature.

Medical thermometers are used in areas where infectious diseases occur. They use far-infrared rays to emit light signals to measure the temperature of the human body without touching the human body. It has special uses during SARS and avian influenza. The temperature is designed to be -50～480℃, and the low temperature measurement of minus 50 degrees is easily realized, and it can also be used normally in low temperature areas such as northeast and northwest. 

Specifications of infrared thermometer

The specifications of the infrared thermometer include accuracy and angle coverage. Simpler instruments may have a measurement error of approximately ±2°C or ±4°F. The dot pitch ratio (D:S) is the ratio of the distance to the measurement surface to the diameter of the temperature measurement area. For example, if the D:S ratio is 12:1, the diameter of the measurement area is one twelfth the distance to the object. A thermometer with a higher ratio of D value to S value can sense a more specific, narrower surface than a larger distance with a lower ratio. A device with a rating of 12:1 can sense a 1-inch circle at a distance of one foot, while a device with a ratio of 10:1 can achieve the same 1-inch circle at 10 inches, while at 10,000 feet. Achieve 1.2 inches wide and the less clear circle distance is 12 inches.

The ideal target area should be at least twice the size of the spot at this distance, which is small compared to the distance, resulting in lower measurement accuracy. The infrared thermometer cannot be placed too close to the target, otherwise this distance will cause heat to accumulate in the thermometer housing and damage the sensor. Due to the influence of reflectivity and the influence of other heat sources in the sensor's field of view, the measurement error usually only decreases as the distance increases.

Professional explanation

According to the Stefan–Boltzmann law, the radiation power is proportional to the fourth power of the temperature. Therefore, when the measurement surface has both hot and cold areas, the indicated temperature may be higher than the actual average temperature and closer to the average of the fourth power.

Most surfaces of infrared thermometers have high emissivity (more than 0.9 for most biological surfaces), and most of them rely on this simplified assumption. However, the emissivity of the reflective surface is lower than that of the non-reflective surface. Some sensors have adjustable emissivity settings, which can be set to measure the temperature of reflective and non-reflective surfaces. Non-adjustable thermometers may be used to measure the temperature of reflective surfaces by applying non-reflective paint or tape, but this will reduce accuracy.

We hope this article has helped you understand more about the accuracy of infrared thermometer box. If you need infrared thermometer, do not hesitate to contact us.