Thermography function and working principle

The function of an infrared thermal imager is to convert infrared heat patterns invisible to the human eye into visually visible television images or photographs. The infrared thermal pattern is a thermal energy pattern formed by different temperature distributions of the measured object and different infrared radiation energy.

The thermal imager works as shown in Figure 12-29. The optical system collects the radiation and, after filtering, collects the thermal image of the scene on the detector. The detector is located on the focal plane of the optical system. The opto-mechanical scanner includes two scanning mirror sets, one vertical scanning and one horizontal scanning. The scanner is located between the optical system and the detector. The scanning mirror swings to achieve the point-by-point scanning of the object, thereby collecting the space of the object temperature. Distribution. When the mirror swings, the beam from the object to the detector also moves with it, forming a one-to-one correspondence between object points and image points. Then the detector scans the optical system point-by-point through the spatial distribution of the temperature distribution of the scene and turns it into an electrical signal arranged in a time sequence. After the signal processing, the display shows the visible image.

Infrared thermometers and infrared thermal imaging cameras have increasingly played a major role in military, space technology, and industrial and agricultural science and technology. In the mechanical manufacturing industry, it has been used in experimental research on machine tool thermal deformation, cutting temperature, and tool life control.