Detailed infrared active and passive dual-mode technology

The research of infrared technology involves a wide range, including the target's infrared radiation characteristics, background characteristics, infrared elements, components and systems; both material problems and application problems. The infrared technology applied in security is mainly divided into active infrared and passive infrared technologies.

Infrared passive mode can irradiate infrared by decomposing all objects. Therefore, using a detector to measure the infrared difference between the target itself and the background can get different infrared images. The thermal infrared image is called the heat map, which is the so-called passive infrared technology. .

The use of different infrared radiation intensity in different parts of the natural objects to form images, has been widely used in the military field. In terms of civil security monitoring, production of infrared thermal imaging related security products was only started in 2007. So far, it has only been used in some special places.

There are three major differences between this technology and active infrared technology. The first is that it can be used in completely dark nights and in harsh environments with rain and snow clouds. It can clearly observe targets and truly monitor it on a 24-hour basis. As a passive non-contact detection and recognition method, it can be identified and has good concealment without direct exposure to objects. The detection distance is also an aspect of active infrared technology that distinguishes the technology clearly. The detection range is as much as tens of kilometers. . The main application of this technology is in ultra-long-range night-vision monitoring of frontier defense, national defense engineering, night vision reconnaissance operations, key military installations, military agencies, military garrisons, and night vision operations and other occasions. The production process and technical requirements for thermal imaging technology and The threshold is very high, not an ordinary enterprise can achieve the production process, which also determines the value of such products, a detector moving tens or hundreds of thousands of dollars, so the application of civilian monitoring is very limited.

Since the thermal imaging technology performs image decomposition scanning on the thermal radiation of an object and then uses a photodetector for light-electricity conversion, the image taken by it has low contrast and poor ability to distinguish details. For example, a security incident requires “strong evidence” Specific people and things are clearly distinguished, so the application of thermal imaging also has a certain limit. Imagine: If you can combine infrared thermal imaging technology and laser infrared technology camera system, I believe it is a very effective application, not only can a large area induction, but also can clearly detect specific people and objects, I believe that in the near future infrared heat The effective combination of imaging and laser infrared will be a new direction of development.

The application of infrared active technology to resolve active infrared is based on LED infrared, array infrared, and laser infrared.

LED Infrared Lamp LED Infrared Lamp consists of an infrared light emitting diode matrix to form a luminous body. The infrared emitting diode is made of a material with high infrared radiation efficiency and made of a PN junction. A forward bias voltage is applied to the PN junction to inject infrared light. The infrared camera produced by using this technology is known for its low manufacturing cost and low technical threshold. At present, most security manufacturers have chosen to use it.

Manufacturers and users of this type of technology all know that the LED infrared light irradiation distance, long-term use of heat dissipation, infrared lamp life, uneven brightness monitoring screen has always been a problem that plagued everyone. At the same time, the application of this infrared technology also has certain limitations. The technology is mainly based on indoor environmental monitoring and outdoor short-range, such as some indoor channels, corridors, rooms, warehouses, etc., like outdoor short-distance trunk roads, corridors, intersections, Entrances and exits are more suitable for smaller and shorter surveillance areas. The performance of LED infrared lamps in these areas can be accepted by the user. To a certain extent, they can also replace the ultra-low illumination camera to achieve night surveillance.

Although many infrared LED manufacturers have improved, life expectancy and the single LED's irradiation distance has greatly improved, but it is still far from meeting the current monitoring needs, so it will eventually escape the fate of being eliminated.

Array infrared light array LED infrared technology based on the original LED infrared technology, using advanced packaging technology, will dozens of high power, high efficiency infrared crystal original packaged in a plane. The appearance of the array infrared lamp makes up for the defects of the LED, and improves the current status of the LED having a short service life, a short infrared night vision distance, and an unfavorable infrared effect. Especially at night surveillance sites with medium and short distances ranging from tens of meters to 100 meters, and monitoring sites with wider monitoring areas, such as road monitoring, factories, communities, prison walls, more open spaces, sports stadiums, etc., in safe cities. .

Using this infrared technology, both the illumination distance and the brightness of the screen are more uniform than LEDs. In terms of irradiation distance, the optical output of an array type infrared lamp can reach about 2W, which is equivalent to the brightness of the traditional 200 LED, and it can truly achieve the actual irradiation distance of more than 100 meters outdoors; in terms of the brightness of the screen Because the original half-power angle of the array-type infrared lamp luminous body is approximately 150°, different angles can be changed by optical means, and the luminous angle can be either large or small, so that the illuminating light beam is evenly irradiated on the target and the brightness of the entire screen is uniform.

In addition, the array type infrared lamp also has great improvement in the service life. The integrated body of the array type infrared lamp is made of metal and has good heat dissipation and is easy to maintain low temperature during operation. Although the technology has been gradually promoted in the market, due to the high cost, it has affected the pace of advancement of this type of product to a certain extent. With the significant reduction in production costs, the technology should gradually become popular in the next one to two years.

Laser Infrared Lamps Laser Infrared lamps are semiconductor lasers that use semiconductor materials to recombine holes and electrons, as well as electrons that release electrons to generate light energy, and then photons form lasers in the direction of the resonance specification photons. . The laser has a good directionality, which is characterized by a small beam angle, energy concentration, and sufficient light intensity to travel far, making it ideal for long-distance lighting.

The distance between conventional products is 100-500 meters and the maximum distance is 3000 meters. Want to monitor the reality of long-distance will need to adopt new technologies, that is, infrared laser night vision technology, such as large-scale environmental monitoring, forest fire prevention, scenic spot monitoring, port terminal monitoring, oilfield monitoring, etc. These areas are mainly characterized by long monitoring distance , It is generally several hundred meters or even one to two kilometers. The monitoring range is relatively large and the risk factor is high. The introduction of laser infrared lamp technology can completely solve the problem of remote night surveillance and achieve long-distance radiation. For monitoring purposes. The laser infrared lamp's production process is not like the LED infrared lamp, and its production process requires very high. At the same time, the production of laser infrared lamps requires a huge investment, which is something that ordinary manufacturers cannot accomplish. The production of laser infrared technology needs to be improved, and the production of finished products needs to be reduced. With the advancement of the market, laser infrared lamps will be as popular as LED infrared lamps in the next three to five years. It will eventually become mainstream infrared night vision products.