Infrared camera night vision fogging is a very common problem. The camera lens is fogged. The reason is that, in addition to the camera itself, it has a lot to do with the environment.
1. Location of fogging
The main two places are on the camera's internal lens and the camera's external glass cover.
2. The cause of fogging
Mainly because the temperature used by the camera is low and the air humidity is high. Infrared camera infrared start at night, the internal temperature of the machine is high, due to the pre-condensation of saturated water vapor in the air into fog, frost, adhere to the infrared camera cover glass or the camera internal lens, resulting in invisible objects.
There is a problem here. Whether the camera is tightly sealed can prevent the generation of fog, or ensure better ventilation and ventilation to prevent condensation from condensing on the internal lens of the camera. Therefore, specific analysis of specific issues is required.
a. fogging inside the camera
There is water vapor inside and the humidity is high. How did the internal moisture vapor come from?
The board used for PCB board, chip board, lamp board, lens, and even the casing is not good, there are impurities, volatile materials, and the ambient air humidity of the assembly is large. At night, the camera starts up in the infrared, the temperature is high, the high temperature causes these impurities, the water vapor evaporates, the camera is sealed better, the water vapor can not be emitted, and it condenses on the internal lens.
1. This situation is generally to increase the defrosting circuit, open the vent, add the fan, put the desiccant and so on. In order to solve the problem fundamentally, it must be strictly controlled before leaving the factory to prevent the existence of volatiles.
2. Circuit board PCB board, chip board, light board, lens, good quality work, no impurities, volatile materials.
3. The opaque ring and the glass should be in agreement. Do not leak light (the lens hood is leaking and not in close contact with the glass, and the infrared light is refracted into the lens).
4. Extend the copying time and keep the inside of the camera dry (not too much moisture in the production environment).
5. Before production, use a high temperature oven to bake the shell, lamp, lens and other accessories at high temperature to remove moisture from these parts.
The external water vapor is mainly due to the lack of waterproofing of the camera.
Improve the production process. First, add a waterproof rubber sleeve, add a water pad at the interface to play a waterproof role; secondly, apply waterproof glue at the screw opening to enhance waterproofness. Generally, the infrared camera adopts an aluminum alloy casing to improve the accuracy of the interface, and is made of high-quality silicone material. The effect is ideal.
b. External fog of the camera
This has nothing to do with the camera itself. The outside air is wet, raining, etc., and the water vapor covers the camera cover glass to block the line of sight.
Solution: Apply a rain brush to the protective cover to clean the glass. Use the invisible wiper window glass. The invisible wiper has the function of repelling water and dust.