A monitor filter is an accessory to the computer display to filter out the light reflected from the smooth glass surface of a CRT or flat panel display.
A secondary use for monitor filters is privacy as they decrease the viewing angle of a monitor, preventing it from being viewed from the side; in this case, they are also called privacy screens.
The standard type of anti-glare filter consists of a coating that reduces the reflection from a glass or plastic surface.
Although effective, a mesh filter also caused degradation of the image quality.
[2] Marketing names of privacy filters: Support for privacy screen is available since Linux kernel 5.17 that expose it through Direct Rendering Manager and is used by GNOME 42.