Centigrade:±0.2°CLess than 35.5°C
±0.2°CGreater than 42.0°C
Fahrenheit:±0.3°FLess than 95.9°F
±0.3°FGreater than 102.2°F
At standard room temperature 25.0°C(77.0°F)
Display: Liquid crystal display 4 digits
Memory: For storing the last measured value
Battery: One 1.5V button size battery (UCC 392 or Lr41)
Power consumption:0.15 milliwatts in measurement mode
Battery life:More than 200 hours of continuous operation
Weight:Approx.11 grams including battery
Is the infrared thermometer reliable?
The non-contact temperature measurement will not infect virus, it is fast and convenient for large-scale application, but is the temperature measured by this simple and fast method reliable?
F. w. huxler, a British physicist, discovered infrared light in 1800 when he studied various colors of light. At that time, he called it "invisible light". Huxler used a prism to decompose the sun's light and put a thermometer on each color of light. It was found that the thermometer at the infrared position had the fastest temperature rise and strong infrared thermal effect. After that, people spent more than one hundred years to understand the electromagnetic nature of infrared radiation, understand and explore the basic laws of thermal radiation. With the continuous development of optical technology and electronic technology, infrared technology is becoming more and more perfect, among which infrared temperature measurement technology is widely used in various fields, and its principle is to use the infrared radiation of the object surface to obtain the measured temperature.
As long as the temperature of any object is higher than absolute zero (- 273 ℃), there will be thermal transformation of thermal radiation emitted outward. Different temperature of the object will radiate different energy, and the wavelength of the radiation wave will be different, but always include infrared radiation. When the temperature of the object is below 1000 ℃, the strongest electromagnetic wave in the thermal radiation is infrared wave.
According to this principle, the basic temperature measurement process of the infrared temperature gun is as follows: the energy emitted by the human body is gathered on the infrared detector through the optical system, the detector converts the incident radiation into the voltage signal, the voltage signal is sent to the receiving system, after the data processing and automatic curve fitting, the measured human body temperature is accurately calculated, and the output is displayed in a digital way.
How to calculate the temperature of the object and what kind of relationship between them?
In the 19th century, scientists Stefan and Boltzmann obtained the blackbody radiation law through experiments and calculations: MB (T) = σ T4 (σ is a constant). This law tells us that the total radiation energy per unit time radiated from the blackbody unit area is directly proportional to the fourth power of its own thermodynamic temperature.
Of course, the radiation law of real objects (non blackbody) is generally complex, which needs to be studied by means of the radiation law of blackbody. It is mainly affected by the emissivity of objects. The emissivity of different objects is different, which can be obtained by looking up tables or experiments. The infrared temperature measuring gun can correct the infrared radiation force error caused by the material, structure, thickness, etc. of the object, and measure it accurately The surface temperature of the object.
Is the infrared thermometer reliable?
If you understand the principle, it can be said that the "infrared thermometer" is actually reliable, but it is not reliable to talk about it without using methods and testing environment.
First of all, from the person in charge of the measurement, the first is that the distance between the infrared thermometer and the forehead should not be too far, otherwise the infrared radiation energy that the infrared detector of the thermometer can collect will be smaller, thus affecting the measurement results. The ideal distance is about 5cm to 8cm from the forehead.
The second is that the infrared temperature gun needs to be vertical to the forehead as much as possible, so as to ensure that the collected infrared radiation energy is emitted from the target measurement area.
The third point has nothing to do with the forehead, because the forehead temperature exposed to the air may be lower than the actual human body temperature, for example, when walking in the cold wind, the lower the temperature, the less the infrared radiation energy. A better way is to measure the wrist covered with clothes, which is believed to be more accurate than measuring the forehead.
The fourth is not to let the infrared temperature gun in the environment with a temperature difference of 20 degrees or higher, otherwise the measured data will be inaccurate. As measured, we can also avoid strenuous exercise or eating too hot or too cold things within 20 minutes to half an hour before the measurement, so as to make the measurement results as accurate as possible.
In general, as long as the infrared temperature gun is used properly, the measured results are still reliable.