Knowledge of non-contact infrared thermometer
1, Why use non-contact infrared thermometer?
The non-contact infrared thermometer uses infrared technology to quickly and conveniently measure the surface temperature of objects. Quickly measure temperature readings without mechanical contact with the object being measured. Just aim, press the trigger, and read the temperature data on the LCD screen. The infrared thermometer is lightweight, small in size, convenient to use, and can reliably measure hot, dangerous, or difficult to reach objects without contaminating or damaging the measured object. The infrared thermometer can measure several readings per second, while the contact thermometer takes several minutes to measure per second.
2, How does an infrared thermometer work?
Infrared thermometers receive invisible infrared energy emitted by various objects themselves. Infrared radiation is a part of the electromagnetic spectrum, which includes radio waves, microwaves, visible light, ultraviolet, R-rays, and X-rays. Infrared is located between visible light and radio waves, and the wavelength of infrared is commonly expressed in micrometers, with a wavelength range of 0.7-1000 micrometers. In fact, the 0.7-14 micrometer wavelength band is used for infrared thermometers.
3, How to ensure the temperature measurement accuracy of an infrared thermometer?
The undisputed understanding of infrared technology and its principles is accurate temperature measurement. When measured by an infrared thermometer, the infrared energy emitted by the object being measured is converted into an electrical signal on the detector through the optical system of the infrared thermometer. The temperature reading of this signal is displayed, and there are several important factors that determine the temperature measurement. The important factors are emissivity, field of view, distance to the spot, and position of the spot. Emissivity, all objects reflect, transmit, and emit energy, only the emitted energy can indicate the temperature of the object. When the infrared thermometer measures the surface temperature, the instrument can receive all three types of energy. Therefore, all infrared thermometers must be adjusted to read only the energy emitted. Measurement errors are usually caused by the infrared energy reflected by other light sources. Some infrared thermometers can change the emissivity, and the emissivity values of various materials can be found in published emissivity tables. Other instruments have a fixed preset emissivity of 0.95. The emissivity value is for the surface temperature of most organic materials, paints, or oxidized surfaces, which needs to be compensated by applying a tape or flat black paint to the tested surface. When the tape or paint reaches the same temperature as the substrate material, measure the surface temperature of the tape or paint to obtain its true temperature. The ratio of distance to spot, the optical system of an infrared thermometer collects energy from a circular measuring spot and focuses it on the detector. The optical resolution is defined as the ratio of the distance from the infrared thermometer to the object to the size of the measured spot (D: S). The larger the ratio, the better the resolution of the infrared thermometer, and the smaller the size of the measured light spot. Laser aiming is only used to assist in aiming at the measurement point. The new improvement in infrared optics is the addition of near focus characteristics, which can provide measurements for small target areas and prevent the influence of background temperature. Field of view, ensuring that the target is larger than the spot size measured by the infrared thermometer. The smaller the target, the closer it should be. When accuracy is particularly important, ensure that the target is at least twice the size of the spot.
