Solve the four application problems of infrared cameras

Infrared cameras are not only satisfied with the low indoor illumination, but also meet the requirements of international energy conservation. Based on these two points, they are widely used in indoor and outdoor environments. In actual use, infrared cameras also have their drawbacks. Commonly there are four major problems.

Focus offset problem

Due to different wavelengths of visible light and infrared light, the imaging focus is not on one plane, resulting in clear images under visible light conditions during the day, blurring under nighttime infrared light conditions, or clear images under nighttime infrared light conditions, and image blurring under daytime visible light conditions. It can be solved in three ways. First, the use of automatic focusing integrated camera; second, the use of IR special focus does not shift the lens; third, the use of professional adjustment tools, under the existing lens conditions can also be achieved without offset.

Color problem

All black and white cameras are infrared-sensitive. Infrared light is a kind of stray light for color cameras in the visible light condition, which will reduce the resolution and color reproduction of color cameras. The filters of color cameras prevent infrared light from participating in imaging. There are two ways to make the color camera sense infrared light. First, switch the filter to block the infrared light from entering under visible light; remove the filter under the condition of no visible light and let the infrared light enter. The image quality is good, but the cost is high and the switching mechanism will cause a certain failure rate. Second, opening a specific infrared channel on the filter allows infrared rays with the same wavelength as the IR lamp to come in. This method does not increase the cost, but the color reproduction is slightly worse.

The problem of sensitivity

Camera sensitivity is a core part of infrared night vision monitoring. The better the sensitivity, the stronger the ability to sense infrared rays. Of course, the better the sensitivity, the more expensive the camera is. In general, an infrared night vision system within 50 meters is better if a camera with 0.1 lux is used; a night vision system with a range of 50 meters to 100 meters should use a camera with 0.01 lux; a night vision system with a distance of 100 meters or more should be 0.001 lux. Above the camera. Of course, as the sensitivity increases, the price of the camera will increase significantly.

The problem of distance

One hundred people will have a standard infrared night vision distance for infrared products. I think it should be based on the effectiveness of the customer's application. What is the customer's standard? It is to see people! What are the "visual distances" and "discovery distances" are all ambiguous. The matching of cameras and lenses in different grades may cause the sensitivity of the light emitted from the same infrared lamp to be many times different, and the visual distance may also be much different. Therefore, it is unscientific to say how many meters a concrete infrared light is. A working distance of an infrared lamp can only be determined by matching the camera and lens of a certain quality. Also, because of the different environments in which the applications are applied, the effects will be very different and it is best to leave a certain margin.