ROMA 1080
Width : 1080mm
Efficient width : 940mm
Thickness : 2.0mm, 2.3mm, 2.5mm, 2.8mm, 3.0mm
Length : customized(times of unit length 328mm)
Purlin distance : 984mm
Aplication : villa, residential roof, etc.
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The technology of realizing the night vision of the camera currently uses the infrared night vision technology. The infrared imaging technology is divided into two kinds: passive infrared camera technology and active infrared camera technology.
1. The passive infrared camera technology uses the principle that any object can radiate electromagnetic waves above absolute zero (-273°C). Due to differences in the radiating ability of different objects and even different parts of the same object and their reflection on infrared rays, the radiation difference between the object and the background environment, and the difference in the radiation of each part of the scene itself, the infrared detector can convert the radiation signals of different intensity into different Corresponding electrical signals are then subjected to amplification and video processing to form video images that can be observed by the human eye. The thermal images can present the undulations of the various parts of the scene and thus can display the characteristics of the scene.
The thermal image and the visible light image of the same target are different. It is not a visible light image that can be seen by the human eye, but an image of the temperature distribution of the target surface. It cannot clearly identify the detailed features of the target and cannot meet the requirement of “evidence†and is passive. Infrared cameras are expensive and mostly used in military applications. Currently, there are few applications in the field of surveillance.
2, active infrared camera technology is the use of "infrared light-emitting diodes" artificially generated infrared radiation, to produce the invisible and ordinary camera can capture infrared light, auxiliary "lighting" scenes and the environment, use the camera's image sensor can feel the infrared light Characteristics, feel the infrared light reflected from the surrounding environment, get a clearer black and white image screen, and achieve night vision monitoring. Therefore, most of the current infrared camera technology uses active infrared camera technology and uses infrared light to match the camera.
Active infrared technology is currently more mature in four forms:
1. Traditional LED Infrared Lamps: The illuminant consists of a certain number of infrared light emitting diode arrays. The infrared emitting diode is made of a material with high infrared radiation efficiency, and a PN junction is made of a material with high infrared radiation efficiency. A forward bias voltage is applied to the PN junction to inject infrared light. The spectral power distribution is center wavelength of 830-950 nm, and the half-peak bandwidth is about 40 nm. It is a narrow band. The distribution is the CCD-sensible range.
2. Second-generation array-integrated infrared light source: based on the original LED infrared technology, advanced packaging technology was adopted, and dozens of high-power and high-efficiency infrared crystals were originally packaged on a single plane and multiple integrated Infrared light-emitting chip in a small area, and made a "thermoelectric separation" process, making the entire part can be placed on any size, arbitrary shape of the heat sink, which solves the heat problem, no longer will hurt the surrounding other electronic due to high temperature Components.
3rd, the third generation lattice type infrared light source: Uses the highly integrated LED array chip technology, the output of the single LEDArray is about 800mW~3.6W, the electro-optical conversion efficiency is about 25%, the luminous body is a single light source, the luminous angle may be large or small .
4. Laser infrared lamp: It is a semiconductor laser that uses semiconductor materials to recombine holes and electrons, and electrons are released to produce light energy by lowering the energy level of electrons. Then, photons form lasers in the propagation direction of the resonant norm photons. . The laser has a good directionality, which is characterized by a small beam angle, energy concentration, and sufficient light intensity to travel farther, making it ideal for long-distance lighting.
Second, the comparison of imaging effects of various infrared technologies
1. Comparison of Active Infrared Technology and Passive Infrared Technology:
Active infrared cameras require the use of infrared transmitters. The advantage is that they can display the details of the target, and the cost is low. The disadvantage is that the distance between them is relatively close and the imaging effect is easily affected by the environment, especially in fog, snow and rain. Under such severe weather conditions, it is mainly used to detect targets.
Passive infrared cameras do not require auxiliary light sources. The advantage is that the penetrating power is strong and the irradiation distance is long; the disadvantage is that only the surface temperature distribution image of the target can be presented, which is mainly used to find the target.
2. Comparison of four active infrared technologies:
1) Traditional LED infrared light, which is currently the most commonly used infrared light-emitting device, which occupies more than 95% of the market, but the quality is uneven, and the price difference is also large;
The advantages are small size, simple production process, easy quality assurance, low heat generation, reasonable light emitting optical system, no red storm (using 940-950nm wavelength) or only weak red storm (red storm has visible red light) With a service life of several thousand hours or more, it is an ideal device for making infrared lamps and is widely used for night vision monitoring.
The disadvantage is poor heat treatment, resulting in too high ambient temperature and affecting the life of nearby electronic components (such as camera boards, control circuit boards, etc.). The most spurious is that its light decays too quickly, and it is generally less than a year to see the night vision screen. Since it is encapsulated with "epoxy resin", "epoxy resin" will break when exposed to heat. After a long time, the fracture surface will be more and more, and some light will be refracted when infrared rays pass through each fracture surface. This is the main reason why traditional LED lights have fast decay and short life.
2) The second generation of arrayed integrated light source, which integrates multiple infrared light emitting chips in a small area, and "thermoelectric separation" processing, so that the entire part can be placed on any size, arbitrary shape of the heat sink, so that The problem of heat dissipation is solved, and no other parts of the surrounding electronic components are damaged due to high temperature. And due to the use of silicone encapsulation, the material does not break and greatly reduce the light attenuation, and the lifetime is 5-10 times longer than the traditional LED lamp.
The disadvantage is that the price is much higher than traditional LED lights. Moreover, in order to reduce the light transmission angle by using a lens to match the angle of the camera lens, it is inevitable that many light points deviate from the center of the lens (commonly referred to as eccentricity), resulting in poor light transmission efficiency, as compared with the same power. For traditional LED lights, "not bright enough" is its drawback.
3) The third-generation dot-matrix infrared light source (LEDArray) has an electro-optical conversion efficiency of about 25%, which is 2.5 times higher than that of the first-generation ordinary infrared LED, and reduces power consumption; the output of a single LEDArray is approximately 800mW ~ 3.6W, the brightness is about 100 times the output of the conventional single LED 5 ~ 15mW; LEDArray effective life is 10,000h, more than 5 times the effective life of ordinary LED; using metal, easy to maintain during operation Low temperature, good heat dissipation performance; LED Array half power angle is 10 ° ~ 120 °, can produce (180 ° shape) of the light-emitting surface, to solve the ordinary LED indoor space can not be uniformly illuminated "flashlight effect"; LEDArray is a highly integrated chip, Therefore, its volume is much smaller than other infrared products under the same brightness index;
The third-generation dot-matrix infrared light source has a price closer to the traditional LED and is currently the best technology in the infrared lighting market, and it is slowly replacing the traditional LED infrared lighting technology.
4) Laser lighting technology, up to 3,000 meters, is more than 20 times that of conventional products (120-150 meters). The laser has good directionality, the beam angle is small, the energy is concentrated, and there is still enough light intensity to spread farther, so it is suitable for long-distance lighting. It is suitable for large-scale environmental monitoring, forest fire prevention, scenic spot monitoring, and port terminals. Monitoring, oilfield monitoring and so on.
However, the production process of the laser infrared lamp is not like the LED infrared lamp, and its production process requirements are very high. At the same time, the production of laser infrared lamps requires a huge investment, which is something that ordinary manufacturers cannot accomplish.
Comparison of imaging effects of various infrared technologies
With the security issues gradually becoming the focus of social attention, the development of security monitoring technology is also increasingly concerned by all aspects of society, only visible light monitoring can no longer meet people's monitoring requirements, 24-hour continuous monitoring is now in the monitoring system must The less important part.