Nowadays, the common infrared waterproof camera generally uses photosensitive elements to detect the lighting intensity of the environment. According to the threshold determined in the design parameters, the control signal is generated to turn on the infrared lamp. The level of threshold depends on the environment of use, the preference of users and the importance of various factors considered by designers. The products of various manufacturers are different. Such as 20,10,5 lux. If the threshold value is high, the start time is earlier. It is possible that the infrared lamp will be turned on before the camera has converted from color to black and white. There are three disadvantages
First, it extends the service life of the infrared lamp of the infrared waterproof camera and affects the service life of the product;
Second, if the infrared lamp is turned on when the color image can be generated, the image quality will be reduced;
The third is to produce infrared eyes on color images (infrared eyes are also determined by the principle, which people do not want to see). If the threshold is low, the infrared lamp may not turn on in time when supplementary lighting is needed.
Why does the infrared waterproof camera flicker? As mentioned before, when the lighting intensity is lower than the threshold, the infrared light turns on. Above the threshold, it is turned off. Let's consider the situation when the illumination intensity is slightly lower than the threshold: when the light sensitive element detects that the illumination intensity is slightly lower than the threshold, it controls the infrared lamp to turn on and emit light. After the infrared lamp emits light, the detected illumination increases (plus the infrared light coming back in the reverse direction), and when it exceeds the threshold, it controls the infrared lamp to turn off. As a result, the detected illumination decreases, and it controls the infrared lamp to turn on again. So back and forth, resulting in the flicker of the image. This situation is due to the principle, not to say normal, at least not the quality of the product.
So how to solve the problem of infrared waterproof camera image flicker? The environmental illumination detected by the photosensitive element is slightly lower than the threshold is the condition of the problem, there are two cases.
1、 At some point in the evening, for a short time, if this problem occurs, if you don't want to add back the cost, you should use ordinary chips, explain the reason to the users and tolerate it.
2、 This problem must be solved when the illumination intensity is stable.
1. Change the threshold.
In the same type of products, the threshold is also different, there are discrete. Maybe the problem will be solved by replacing a batch of products.
Products with different design thresholds are provided by the manufacturer for replacement. The products with higher threshold design parameters are less likely to flicker.
2. Change the environment
Change the intensity and angle of lighting, slightly change the installation angle of the infrared waterproof camera, move up and down, left and right, the illuminance detected by the detector will change a lot, and it will leave the threshold, so as to solve the flicker problem.
3. The camera chip with high quality and low illumination, backlight compensation and anti strong light, especially the special IR lens, is adopted. In addition, when someone or other objects near the infrared waterproof camera reflect the infrared light, the detected illumination will change repeatedly, causing flicker. For example, in the demonstration test and detection, when the camera is installed at a low position and there are objects close to block the camera.
This is not a problem. When the infrared waterproof camera is in the normal installation position, this phenomenon will naturally disappear. Such as demonstration, as long as pay attention not to let the infrared light from a very close distance directly reverse to the photosensitive element.
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