Introduction to the working principle of high-speed infrared thermometer
The high-speed infrared thermometer is composed of optical system, photodetector, signal amplifier, signal processing, display output and other parts. The high-speed infrared thermometer measures infrared radiation energy through infrared detectors (thermal detectors and photoelectric detectors) and converts it into electrical signals, and then converts it into temperature according to the basic law of radiation.
The optical system collects the target infrared radiation energy in its field of view, and the size of the field of view is determined by the optical parts and position of the thermometer. Infrared energy is focused on a photodetector and converted into a corresponding electrical signal. The signal is transformed into the temperature value of the measured target after the amplifier and signal processing circuit are calculated according to the algorithm inside the instrument and the target emissivity is corrected. In addition, the environmental conditions of the target and the thermometer should also be considered, such as the influence of factors such as temperature, atmosphere, pollution and interference on the performance indicators and the correction method.
The high-speed infrared thermometer is used to measure the surface temperature of the object. The emitted, reflected and transmitted energy of the optical element of the thermometer is concentrated on the detector. The electronic component of the thermometer converts this information into a temperature reading and displays it on the on the display panel of the thermometer. The temperature displayed by the infrared thermometer is often called the brightness temperature of the target, which is different from the real temperature of the object, because the emissivity of the object has a certain influence on the radiation temperature measurement, and almost all the actual objects in nature are not black bodies. The radiation amount of all actual objects depends not only on the radiation wavelength and the temperature of the object, but also on the type of material constituting the object, the preparation method, the thermal process, the surface state and the environmental conditions. Therefore, in order to make the law of black body radiation applicable to all practical objects, a proportional coefficient related to material properties and surface states must be introduced, that is, emissivity. This coefficient indicates how close the thermal radiation of the actual object is to the black body radiation, and its value is between 0 and 1. According to the law of radiation, as long as the emissivity of the material is known, the infrared radiation characteristics of any object can be known
