If you want to learn the working principle of IR-cut for your camera, please refer below.
Applies to: All Reolink cameras
During the day, the IR filter is switched on. It will block infrared light and only allow visible light to pass through. This ensures it does not distort the image colors, generating true color representation – exactly as the human eye sees them.
In the night (or in low-light conditions), the IR filter is switched off, so IR and all other forms of light will be allowed to reach the sensor (CCD/CMOS). The image sensor can absorb sufficient light and the camera will turn to black-and-white mode, which is more sensitive to infrared.