One of the problems with old CRT monitors over time was a condition called burn-in. This phenomenon resulted in an imprint of an image on the screen that was permanent, caused by the continuous display of a particular image on the screen for extended periods of time. A malfunction of the phosphor on the CRT results in the image being burned into the screen, hence the term. Is there such a thing as LCD screen burn-in?

LCD monitors use a different method to produce the image on the screen and are immune to this burn-in effect. Instead of phosphors generating light and color, an LCD uses a white light behind the screen with polarizers and crystals to filter the light to specific colors. While LCDs are not prone to burn-in like CRTs, LCDs do suffer from what manufacturers call "image persistence."

Similar to burn-in on CRTs, image persistence on LCD monitors is caused by the continuous display of static images on the screen for extended periods of time. Long-term static images cause the LCD crystals to develop a memory of their location to generate the colors of that image. When a different color appears in that location, the color will be different and appear as a faded image from what was previously displayed.

The persistence is a result of how the crystals in the screen work. The crystals move from a position that lets all the light through to a position that doesn’t. It’s almost like a shutter on a window. When the screen displays an image for an extremely long time, the crystals can switch to a certain position. It may shift a little bit to change the color, but not all the way, resulting in a different display than intended.