Why use infrared cutting on the camera?

The reason for using IR-CUT on the camera is that the camera will have different effects during the day and at night due to different light. There is sunlight during the day, mainly visible light. This is the colorful world you see now. Another part of light, such as infrared light, is invisible to the naked eye, but the photosensitive chip of the camera can perceive and reflect. Therefore, the image effect will be color cast. This requires a filter to filter out the light we don't need.

At night, we need as much light as possible to enter the camera to reflect the image. Most cameras turn black and white when the light is bad. At this time, there is no problem of color cast. During the day, we use filters to filter infrared light. Be sure to use an inductive filter at night to let infrared light into the camera as much as possible. In this way, IR-CUT appears, and the filter can be switched according to the change of light.

The IR-CUT double filter means that the camera lens group has a set of filters built in. When the infrared sensor outside the lens detects the change of light intensity, the built-in IR-CUT automatic switching filter can automatically switch according to the intensity of external light, thus achieving the best image effect. In other words, the dual filters can automatically switch filters during the day or night, so the best imaging effect can be obtained during the day or night.

CCD or CMOS, the imaging component of the camera, can see most wavelengths of light. Due to the participation of all kinds of light, the color restored by the camera is different from that seen by the naked eye. In order to solve the color difference problem, the current scheme is to stick one or more layers of bimodal filters in front of CCD (allowing visible light and infrared light to pass through at the same time).

During the day, stray light such as infrared light entering CCD will interfere with color reproduction, such as green plants turning gray and red clothes becoming lighter (especially in sunny outdoor environment); At night, due to the filtering effect of bimodal filter, CCD can't make full use of all the light, and the noise and its low illumination performance are not satisfactory.

In the infrared cut-off double filter switcher, when there is enough light in the daytime, the infrared cut-off filter works and the CCD restores the true color. When there is insufficient light at night, the infrared cutoff/absorption filter automatically moves away, and the full transmission spectral filter starts to work, so that the CCD can make full use of all the light, thus greatly improving the low light performance.