Privacy filter

A privacy filter is a thin, darkened film that attaches to the front of a monitor and narrows its viewing angle, so the screen appears normal when viewed straight on but looks dark or blank when viewed from the side. It is designed to stop people walking past a desk, or sitting nearby, from easily reading what is on screen.

In a home office, this matters most for video calls with a window or hallway behind the screen, shared living spaces where a desk faces a common area, or work involving sensitive documents on a shared or open-plan setup. Filters also cut down glare somewhat as a side effect, since the darkened layer reduces the amount of reflected light bouncing off the screen.

The main trade-off is a dimmer picture and lower color vibrancy compared with an unfiltered monitor, since the filter is essentially a layer of tint sitting on top of the display. Fit also matters, since a filter cut for the wrong screen size or aspect ratio will not align cleanly with an ultrawide or unusually shaped monitor, leaving gaps at the edges.