The purpose of an IR cut filter is to

An IR cut filter is used to block infrared light during daylight hours to prevent it from interfering with the camera's sensor. This ensures that the colors captured by the camera appear natural. Without an IR cut filter, the infrared light can cause color distortions, resulting in unnatural-looking images. Axis cameras equipped with IR cut filters switch between day and night modes to optimize image quality in various lighting conditions, as explained in their technical documents and user manuals.