A burn-in effect of a display is when the emitting phosphors of the screen decrease in luminosity and can no longer be degenerated.
Burn-in effects occur when one and the same working mask is displayed on the screen for a longer period of time and burns into the phosphor. Since the brighter parts of the image have a higher light emission, they are more at risk. The phosphors are then damaged by the continuous emission, resulting in a disturbing, partially different screen brightness. This also shortens the service life of the display. Newer displays are more affected by the burn-in effect in the first hundred operating hours than afterwards.
The burn-in effect occurs with cathode ray tubes and plasma displays and is stronger the longer the screen is operated with the same mask. To prevent this, the displays have screen savers and switch the display to an energy-saving operating mode after a certain period of time. LED displays and OLED displays also have the burn-in effect, but to a much lesser extent than cathode ray tubes.