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| Infrared night vision surveillance systems analysis of common technical problems |
| Date：[
2011/8/22 ] Clicks：19320 Publisher：paishian |
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| Infrared night vision surveillance systems common technical problems of infrared night vision camera; market to determine the technology, in China, due to strong market demand, infrared night vision in this field, Chinese companies have taken the forefront in the world, the popularity of infrared technology to use foreign counterparts hope to make dust. Although there are a number of advanced technical solutions proposed, but not yet stable, mature products to occupy the high-end market. Infrared night vision on the monitor is in the common technical problems explain, look for projects and users for use of infrared night vision surveillance mature to provide a reference. The first is that the distance from the identity of the infrared light is misleading if there is a scale, a fixed exposure distance. Light is actually a kind of energy is spread out with increasing distance to, and not to a sudden there is no distance, but weaker strength, not easy to be identified and tested. Infrared light with infrared light from a real decision is only a part of the role of detection and identification systems to large, double the power of infrared light, volume, power consumption, cost, weight will increase exponentially. But the detection part of the improved performance is not, a better lens, a more sensitive camera will bring a qualitative improvement. Affect the results of the site environment is not easy to change the user's subjective evaluation of night vision system with the understanding there is a change. As a former two main factors, light source and detector system identification is a major part of the variable part of the technical program infrared light and infrared light source array, the difference between the current mainstream technology solutions have infrared heat source and heat source LED technology for efficiency is low, great heat, life is short, high consumable prices, impact of the poor, start delay, intense heat radiation and other issues, is the glory of the past. Is a vibrant mainstream products, whether laser or a single package of conventional LD ordinary LED, there is a large package of high-power LED, there are several small package LED, a new name from the array. All because of performance, features, price, creative features and functionality such as a certain share of the market share of infrared night vision camera life problems life is determined by the design, heat is the most critical, there is heat and control the heat from the heat two level. Water issue is a major mortality issues, problems and misuse of lightning voltage problems, the problems surrounding materials, mainly housing bracket, wire infrared night vision cameras, the choice of conventional ordinary LED, 2, more than a small chip LED, 3, single-chip high-power LED, 4, multi-chip LED large-chip LED chip production process is simple, easy to guarantee quality, low heat, light optical system is reasonable, the infrared light is the ideal device to do, in theory, life can be 10 thousand hours multi-chip LED has two forms, one is the chip that contains 4-8; the other one is the array of light emitting chip, the chip contains 10-30. Why do more chips? Some manufacturers of the theory from: infrared radiation from the light energy is not enough because not enough, more chips together, of course, energy is large, assuming that the light farther. Of course, longer distances require more energy. Small multi-chip LED (array) because of its inherent shortcomings of the structure is not the focus of light, light-emitting optical system is irrational, there is light efficiency is relatively low, the advantage of not effectively play. Such as array LED, currents up to 1000mA, basically just a penny coin size, heat dissipation becomes a problem. LED fear most is the high-temperature work. Meanwhile, the multi-chip LED production requires very strict, and every single chip can not have a little difference in performance, otherwise it will form a weak point, it will spread to a chip broken machine. Overall, relative to the single-chip LED, multi-chip LED's life is not enough. Especially the heat is the key. The case of multi-chip power is the same, hotter, more harsh working environment. Single-chip LED lamp life is a matter of fact, can do very long. That which for many reasons, such as some low level LED chips, excessive impurities; some production technology, however, there is leakage phenomenon; some super-power use, rated 20mA, 50mA or more is used; some do not protect the circuit, or circuit design is unreasonable, which will lead to single-chip LED infrared lights quickly broken. To ensure the life of an infrared lamp, the LED chip to use high-grade. High-grade chips, high efficiency light, light power, consistency, heat is relatively small, of course, the price should be high 2, the optical system design should be reasonable, the light distribution should be reasonable, higher utilization, reduce unwanted reflections, higher anti-dust capabilities. 3 easy to clean, heat must be reasonable and lower thermal resistance, install ventilation to prevent dust from entering, but also necessary to seal the heat quickly 4, to strictly control the operating voltage. LED is a current-sensitive component of the voltage, the voltage slightly higher current increases dramatically, it will burn the LED die instantly; and the voltage is slightly lower then the amount of light will be greatly reduced. Best to use 220-volt infrared lamp. Professional manufacturer specialized in producing high-quality match specific constant current switching power supply, the current changes caused by temperature change to compensate. AC input voltage from 170 volts can be done to 250 V constant voltage can be regulated to adapt to the harsh environment power supply 5, annex part of the input power line against the best selection of high / low temperature, relatively soft anti-bending. Manufacturers of infrared light, the input power line can be 60 degrees below zero at low temperature, high temperature 100 degrees above zero normal use, good night vision system moves when bending the wire will not be able to better withstand the environment of the aging of the wire the damage. Only such products can be long-term use. |
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