With the development of thermal imaging technology, infrared thermal imaging
cameras have been successfully used for security monitoring. In some complex
monitoring scenarios, it has more obvious advantages than general infrared
monitoring equipment. Using the advantages of infrared thermal imaging cameras
to search for targets in a large area at a long distance, this application
greatly meets the long-distance and large-scale monitoring and detection
requirements of night vision monitoring in the security industry. So, what is
the working principle of the infrared camera in the security monitoring?
The working principle of an infrared thermal imager is because it does not require the assistance of an external light source, but instead receives infrared radiation (related to the temperature of the object itself) generated by the object, that is, captures the temperature of the object to image. Although infrared radiation (IR) cannot be observed with the naked eye, an infrared thermal imaging camera can convert it into a visible light image, depicting the temperature change of the measured object or scene. Any object with temperature will emit infrared rays, and the higher the temperature of the object, the greater the amount of infrared radiation. The thermal imager is to receive the infrared rays emitted by the object, display the temperature distribution on the surface of the measured object through a colored picture, and find out the abnormal point of the temperature according to the slight difference in temperature, so as to play a role in maintenance. It is also generally called an infrared camera.
The core is a thermal imager, which is a sensor that can detect extremely small temperature differences and convert the temperature differences into real-time video images for display. But only the thermal contours of people and objects can be seen, and the true colors of the objects cannot be seen clearly.
The infrared energy emitted by an object is focused on the infrared detector through an optical lens. The detector sends information to the sensor electronic components for image processing. The electronic components translate the data sent by the detector into a viewfinder or standard video surveillance. The image viewed on the monitor or LCD monitor.
Infrared thermal imaging is a technology that can convert infrared images into thermal radiation images. This technology can read temperature values from the images. Therefore, each pixel in the thermal radiation image is actually a temperature measurement, which can realize non-contact measurement of the surface temperature of the object.
The structure of an infrared camera is similar to a digital video camera. The main components include a lens that directs infrared radiation at the detector, as well as software and electronic equipment for processing and displaying thermal signals and thermal images.
Natural light is composed of light waves with different wavelengths. The visible range of the human eye is roughly 390-780nm. The electromagnetic waves shorter than 390nm and electromagnetic waves longer than 780nm cannot be felt by the human eye. Among them, electromagnetic waves with wavelengths less than 390nm are outside the violet of the visible light spectrum and are called ultraviolet rays; electromagnetic waves longer than 780nm are outside the red of the visible light spectrum and are called infrared, and their wavelength ranges from 780nm to 1mm.
Thermal imaging monitoring advantages:
1. Target monitoring at night and under severe weather conditions.
At night, the environment is not illuminated by sunlight, you can't see your fingers, and the dim light of street lights is faintly visible. In addition, many targets are not illuminated by street lights at all, making it difficult to see the targets clearly. If an infrared thermal imaging camera is used, the visual difficulties caused by the dark night can be overcome. The working principle is to automatically receive the infrared heat radiation emitted by the target under test. Especially in bad weather conditions, it can still perform the operation on various targets, personnel, vehicles, etc. monitor.
2. Fire protection monitoring.
The biggest function of the thermal imaging camera is to measure the temperature of the target. Therefore, when a fire alarm occurs, it can quickly find the precise location of the fire by receiving infrared heat radiation. The thermal imaging camera can wear even in the vast smoke. Through the layers of smoke, the fire point was found, helping to put out the fire in time.
3. Recognition of camouflage and concealed targets.
When the police need to track some targets during case investigations, these fugitives are often hidden in the grass and woods, and they are difficult to find with the help of visual barriers. Infrared thermal imaging cameras can come in handy at this time by monitoring those higher than the surrounding environment. With a constant temperature of the human body, the target track will no longer be hidden, which greatly reduces the search labor cost and saves the search time.
Good use of the working principle of infrared thermal imaging cameras will only help the development of security work. The thermal imaging camera has become a good partner for people’s security work because it is like a talking machine that continuously records target temperature data, generates images for analysis by relevant personnel, and can instantly find the target when needed Accurate monitoring.