Definition - What does Burn-In mean?
Burn-in is permanent discoloration which can occur on areas of an electronic display. Burn-in often occurs in cathode ray tube displays, especially ones based on older CGA and EGA CRT technology; this is due to the cumulative non-uniform usage of pixels. Methods such as screensavers and switching off the display when not in use are used to prevent burn-in.
Burn-in is also known as screen burn, image burn or raster burn.
Techopedia explains Burn-In
Burn-in usually occurs when a non-moving image is displayed on a monitor for a long period of time. This results in the burning of phosphors in the monitor, with the image often faintly visible even after the display is switched off. Burn-in occurs due to the light-emitting pixels decaying over time, losing their coherency and color accuracy. The effects of burn-in are immediate and cause continual degradation of image quality.
The length of time required for burn-in to set in depends on a number of factors such as the quality of the phosphors used in the display, the amount of time used to display images and the degree of non-uniformity of sub-pixel usage. Modern displays are less susceptible to burn-in, as they have features developed to minimize the issue. One such feature commonly used is known as pixel shifting, which shifts the image on the screen so that pixels are frequently refreshed and changed. Turning off the monitor when not in use as well as use of screensavers in the case of computer displays can also help in minimizing the risk of burn-in.