The Working Principle of IR thermal camera

An infrared thermal imaging camera is a type of camera that displays images by receiving infrared radiation emitted by objects. Any object with a temperature emits infrared radiation. The thermal imager receives the infrared radiation emitted by objects and displays the temperature distribution of the measured object's surface through colored images. It identifies temperature anomalies based on small temperature differences, thus playing a role in maintenance. It is generally also referred to as an infrared thermal imager.

Advantages of Infrared Thermal Imaging Cameras

1. Passive Non-Contact Detection: Infrared thermal imaging technology is a passive non-contact detection and identification technology with good concealment. Compared to infrared fill light products, it avoids phenomena like infrared exposure and easily achieves covert monitoring.

2. Wide Application in Various Conditions: Infrared radiation is the most widely present radiation in nature. The atmosphere, smoke, and clouds can absorb visible light and near-infrared light, but they are transparent to infrared light in the 3-5μm and 8-14μm wavelengths. Therefore, using these two wavelength windows, targets can be clearly observed in completely dark nights or in harsh environments such as rain, snow, or dense smoke. Due to this feature, infrared thermal imaging technology can truly achieve 24/7 all-weather monitoring.

3. Intelligent Video Monitoring and Identification: It can intelligently monitor and identify camouflaged and concealed targets. Camouflaging is mainly for avoiding visible light observation. For example, criminals often hide in bushes and forests during criminal activities, which may lead to incorrect judgments due to the harsh outdoor environment and visual illusions. However, infrared thermal imaging cameras passively receive the thermal radiation emitted by targets. When humans and vehicles are concealed in bushes and forests, their temperatures and infrared radiation are generally much higher than those of plants. Therefore, they can be easily automatically identified. Moreover, ordinary surveillance cameras cannot see objects hidden under the surface of a luminous object. For example, buried stolen items cannot be effectively detected and identified. However, infrared thermal imaging cameras developed using infrared thermal imaging technology can detect and identify them because when the surface of a place is disturbed, its thermal profile will also be disrupted, such as the thermal radiation of overturned soil being different from that of compacted soil. Therefore, this feature of infrared thermal imaging cameras can help find buried stolen goods.

4. Direct Display of Surface Temperature Field: Infrared thermal imaging technology can visually display the temperature field on the surface of an object without being affected by strong light. Infrared thermometers can only display the temperature of a small area or a single point on the surface of an object, while infrared thermal imaging devices can simultaneously measure the temperature of various points on the surface of an object, directly displaying the temperature field of the object's surface in image form.

Infrared thermal imagers, with their concealed detection function, no need for illumination, ability to penetrate dense smoke, fog, and other harsh conditions, and visible distance of several kilometers, have gradually been widely used in security (counter-terrorism) systems, becoming an indispensable part of security monitoring systems. For densely populated public places such as bus stations, train stations, and airports, the inspection and monitoring with infrared thermal imagers can effectively provide early warnings to prevent security incidents. Infrared thermal imaging technology, by sensing the infrared radiation emitted by objects, can quickly and accurately detect heating items such as fire sources and prompt alarms, notifying security personnel to rush to the scene and control suspicious individuals carrying heat sources.