Analyze why the infrared camera screen will appear snowflake points

Infrared cameras are actually integrated monitoring devices such as surveillance cameras, protective covers, infrared lights, and power supply cooling units.

At present, the most commonly used infrared waterproof camera in surveillance engineering is active infrared. The infrared light is emitted by LED. The spectral characteristics of infrared light can be felt by using ccd or cmos, and the infrared light is used as the "illumination source" for night vision imaging.

Below, let's take a look at the reasons and solutions for the infrared camera appearing at night.

Due to its particularity, infrared cameras are quite strict during installation and matching. If the operation is not proper, the infrared camera has a lot of snow spots in addition to the usual whitening and glare. In the evening, it is like snow in the world. At the beginning, we felt incredible, and made a special trip to the electronic security market specializing in infrared. I took a few brands and tried it. If it wasn't, the daytime effect would be mixed. At night, the snow fluttered; so, we did various experiments, tried to change the infrared light and the circuit board, and tried to change to ccd. I have also been to different places to experiment.

Later, the summary of the situation of snowflake points has the following reasons.

First, the infrared camera current shortage causes the snow point to occur. Some outdoor short-distance use of centralized power supply 12v is very convenient, but if it is a long distance, it is not suitable to use the switch power to carry out centralized 12v power supply; because the long-distance infrared lamp generates a large amount of heat, the instability of 12v power supply may result in insufficient power; There is no built-in heat sink that is prone to burnout in the case of unstable current;

Second, the current decays quickly, which may cause the infrared light to fail to work properly. The CCD illumination is relatively high and the infrared light is not received, so the snow flutters;

Third, the infrared camera infrared light quality is poor, the angle of the infrared light and the infrared distance do not match the lens, causing the snow to float. Many companies use a variety of different angles of light to mix and match their own purchases and installations. The advantage of using them is that they can barely use different millimeter-sized lenses. The downside is that people always feel the lights. Angle and distance are not suitable for the lens. When the angle is not suitable, flashlight phenomenon or narrow electric phenomenon is easy to occur; when the distance is not matched, for example, if you use a 12mm lens, but use a light of ten to twenty meters, then you will There will be gray phenomenon; the distance is a bit confusing, the snow is fluttering nearby; and the inferior infrared lamp, in addition to the decoration, the more lights, the more problems, the more concentrated the lamp, the greater the calorific value, the easier Burn out

Fourth, the craft problem: when many people are hand-made, the infrared light is not concentrated, astigmatism; scattered light causes light everywhere, but a gray phenomenon; the front end of the infrared light is not tight, concentrated infrared red The lamp is therefore a vast phenomenon;

Fifth, the built-in is a low-infrared camera with high illumination. Many factories use the same infrared light to obtain brighter images, artificially increase the sensitivity of ccd; because many manufacturers use it for price competition. Inferior camera built-in inside, this kind of camera in the case of insufficient fill light of the infrared light, in order to mention brighter, so artificially increase the gain sensitivity of ccd, as we adjust the brightness on the hard disk recorder, it is very easy to appear snow phenomenon of;

Sixth, the circuit design is unreasonable; we produce infrared cameras, not only to install the infrared light directly into the camera and then on the line, but to redesign and age the camera circuit before loading. Many small-scale processing plants on the market use cheap electronic components, buy cheap infrared lamps, solder them directly with electric soldering irons, and do not redesign or aging the circuits. Other factories that do low-end products, in order to save money, The control board of the control circuit board is removed or integrated with the light board, which easily leads to the infrared lamp being unstable due to current instability, so that the inferior infrared lamp can not work normally;

Seventh, another possibility is that in the case of dusty outdoor, especially in the wild, it is possible that the infrared light in the camera photographed the fine particles that are invisible to the naked eye, which is not in the daytime infrared light. In the case of opening, the inner eye and the camera do not feel obvious; this is the environment;

In summary, there are many reasons for the number of snowflakes, but the method is always more difficult. As long as the real reason is found, it is much easier to solve. As long as you are willing to spend the cost, take the time:

First, use a highly stable transformer to solve the problem of insufficient current; use a multimeter to test the voltage and current to ensure that the infrared lamp works normally;

Second, use high-quality infrared lamps; this is equally important, infrared lamps are not good, no matter how good current is used;

Third, replace the poor camera inside. It is possible that the illuminance of the camera is extremely high, and in the case where the outdoor brightness is not high, snowflake is highly prone to occur; black-and-white cameras or color-to-black-and-white color cameras are used;

Fourth, the use of double filter sheet or double glass structure to improve the intake of infrared light at night and the effective impact of water mist on the lens;

Infrared cameras have to solve the following difficulties:

1. After installing the infrared lamp, it is necessary to reset the circuit and aging; pay attention to the manual problem, pay attention to the problem that the infrared lamp angle has concentrating; this requires the installer to have considerable sense of responsibility and patience.

2, the built-in camera must have a minimum of 0.1 illuminance, otherwise it is easy to appear snow; this requires manufacturers to have the necessary investment and serious determination.

3. The infrared light of the long-range infrared camera generally has a relatively large power. Generally, a 220v-powered camera with a built-in high-quality transformer and a fan is used.

4, to use high-quality infrared light, to prevent the excessive power of the infrared light glare or whitening phenomenon; resulting in unclear or gray image; pay attention to the angle and distance of the infrared light, but also pay attention to its life.

5, to prevent astigmatism and excessive light collection, astigmatism is prone to white, and the collection of light is prone to flashlight phenomenon.