What are the precautions for infrared night vision surveillance cameras? Eight points for attention of infrared night vision surveillance camera

Monitor is a very common monitoring tool in our life. It is designed for security and evidence collection. In our daily life, supermarkets, restaurants and even companies or families are equipped with monitors. For night monitoring, different high-end monitoring tools are needed, and infrared night vision monitoring camera is one of them. As the name implies, the infrared night vision surveillance camera is used as a night surveillance camera. Then, use infrared night vision to monitor the camera. Next, Bian Xiao will give you popular science.

Red storm problem

Some manufacturers advertise that it is a technical problem to make infrared lights without red storms. It seems that red storms are low-tech and non-red storms are high-tech. In fact, whether there is a red storm is only a matter of choice, not a technical problem. Light with a wavelength of more than 700nm is called infrared light, and infrared light with a wavelength of more than 900nm basically has no red bursts. The shorter the wavelength, the stronger the red storm and the higher the infrared sensitivity. At present, there are two mainstream infrared lamps in the market, one is reddish with a wavelength of about 850nm, and the other is non-red with a wavelength of about 940nm. The sensitivity of the same camera at 850nm is better than that at 940nm 10 times. Therefore, the 850nm infrared lamp with slight red storm is more efficient and should be the first choice for infrared night vision monitoring. ?

Life problems?

The service life of the camera can reach 10 years or more. Can the life of infrared lamp reach this level? To answer this question correctly, we must first understand the manufacturing principle of infrared lamps at present. At present, there are three main modes of infrared light: 1, halogen lamp, 2, multi-chip LED, 3 and single-chip LED. Halogen lamp is a traditional technology with high energy consumption, high calorific value and short service life. Because of low efficiency, it is estimated that it will gradually fade out of the market.

In order to ensure the life of infrared lamp, first of all, we should choose high-grade LED chip. High-grade chips have high power, good consistency, high luminous efficiency and low calorific value. The quality of a high-grade LED is 10 times better than that of an ordinary LED, but it is also expensive. Secondly, the optical system design should be reasonable, the light should be uniform, the utilization rate should be high, and the heat dissipation should be fast. Third, we must strictly control the working voltage. LED is very sensitive to voltage, and the LED die will burn if the voltage is slightly higher. When the voltage is slightly lower, the light emission will be greatly reduced. It is best to match high-quality switching power supply, and the AC input voltage should be adjusted between 170V and 270V to adapt to the harsh power supply environment. Fourth, the input power cord should be resistant to high and low temperature, super soft and bending. There is an infrared lamp produced by a manufacturer. The input power cord can be used normally at a low temperature of minus 60 degrees and a high temperature of minus 250 degrees. Cables at MINUS 40 degrees and 50 degrees are still as soft as silk. This product is trustworthy. ?

Angle problem?

Is the viewing angle of infrared lamp wider? Both manufacturers and engineers take this statement for granted. They think that the greater the emission angle of infrared light, the greater the room for choosing a lens, and there will be no "flashlight" phenomenon when choosing a wide-angle lens. So everyone is desperately talking about how big their infrared light angle is. This seemingly reasonable statement is actually very unscientific.

The emission angle of infrared lamp is both a choice problem and a technical problem. For lenses with different focal lengths, infrared lamps meeting the emission angle should be selected. Under any conditions, the emission angle of the infrared lamp should not be larger than the lens angle, but for the application in narrow environment, the infrared lamp should be selected to be smaller or even one third smaller than the lens angle. Narrow-angle infrared lamps can obtain an ideal wide-angle effect with better effect and lower cost by matching.

The luminous flux problem?

The relative aperture determines the light passing ability of the lens. The lens with the relative aperture of F 1.0 has four times the light transmission capacity of the lens with the relative aperture of F2.0 For the same camera, the infrared lamp can double the infrared range by using the above two lenses respectively.

Large-aperture lens is four to ten times better than conventional ordinary lens in infrared monitoring, and it should be a necessary supporting product for infrared night vision monitoring. However, due to the high cost and technical difficulty, most infrared product manufacturers do not have the supply capacity.

Focus shift problem?

Because of the different wavelengths of visible light and infrared light, the imaging focus is not on the same plane, which leads to the clear image under the condition of visible light during the day and blurred image under the condition of infrared light at night, or clear image under the condition of infrared light at night and blurred image under the condition of visible light during the day. There are three ways to solve it. First, adopt an automatic focusing integrated camera; Secondly, the infrared special non-focus lens is adopted; Third, professional adjustment tools can be used to achieve no offset under the existing lens conditions.

Color problem?

All black and white cameras are sensitive to infrared light. Infrared light is a kind of stray light of color camera under visible light, which will reduce the clarity and color reproduction of color camera. The filter of color camera is to prevent infrared light from participating in imaging. There are two ways to make a color camera sense infrared rays. First, switch filters to block infrared rays from entering under visible light conditions. When there is no visible light, remove the filter and let infrared light in. This scheme has good image quality, but the cost is high, and the switching mechanism will lead to a certain failure rate. Secondly, a special infrared channel is opened on the filter to let in infrared light with the same wavelength as the infrared lamp. This method does not increase the cost, but the color reproduction is slightly worse.

Sensitive issues?

Camera sensitivity is the core of infrared night vision monitoring. The better the sensitivity, the stronger the sensitivity to infrared rays. Of course, the better the sensitivity, the more expensive the camera. Generally speaking, the infrared night vision system within 50 meters is best to choose 0. 1 lux camera; The night vision system within the range of 50m to100m should use 0.0 1 lux camera; /kloc-The night vision system above 0/00 meters should use a camera above 0.005438+0 lux. Of course, with the increase of sensitivity, the price of the camera will also increase greatly. ?

The problem of distance?

When one hundred people make infrared products, there will be one hundred infrared night vision distance standards. I think it should be based on the application effect of customers. What are the standards of customers? Is to see people clearly. What are "visible distance" and "discovered distance"? These uncertain statements are ambiguous. The light perception emitted by the same infrared lamp, the matching of cameras and lenses of different grades may be many times different, and the sight distance may also be many times different. So it is unscientific to say how many meters a certain infrared lamp is. The working distance of infrared lamp can only be determined by matching with a certain quality camera and lens. Also, because the application environment is different, the effect will be very different, so it is best to leave a certain margin.

The above are the precautions for the use of infrared night vision surveillance cameras compiled by Bian Xiao. I wonder if you have a better understanding of infrared night vision surveillance cameras after reading them? In fact, infrared night vision surveillance cameras are widely used in our lives. Everyone should try to understand and learn some related knowledge, so as to use it more correctly and conveniently. Of course, some of these things will vary from person to person and depend on the actual situation.

Tubatu Online provides you with "every decoration quotation, 1-4 local decoration companies, 3 sets of decoration design schemes" and the decoration pit avoidance strategy for free! Click this link:/Zhu Ye /zxbj-cszy.php? to8to _ from = SEO _ zhidao _ m _ jiare & amp； Wb, you can get it for free ~