Image retention

Image retention is also known as image persistence, image burn-in or image sticking.
All these terms are used to describe the phenomenon in which static images that have been shown on a display for a long time remain visible as ghost images when the display is turned off or when another image is shown.

Image retention can occur on all types of displays like CRT, VFD, LCD or plasma, with different grades of sensitivity. CRTs are more sensitive than LCDs.

The main reason for image retention in LCDs is impurities of ions in the liquid crystals.
Even though LCD producers put great effort in making purer liquid crystals, till the present day image retention still exists.

The time it takes for an image to “burn in” depends on several factors like image pattern, contrast, brightness, temperature and variations in production batches.
In most cases the ghost images can be removed from LCDs.

One procedure for removing this persistence is to display a totally white screen for a certain period of time.
We suggest showing the white image for at least the same amount of time as the static image was shown that caused the persistence.
One way of achieving this is to create a drawing in a graphics application like paint or Photoshop. Choose the dimension the same as the dimensions of the display. Fill the drawing with white (R:255, G:255, B:255).
This image can be set as screen saver and the system should be left alone to display this screen saver for a period of time. Make sure the monitor settings will not turn off the backlight after some time of inactivity.
Another way of achieving the same effect would be to create a PowerPoint presentation with one totally white slide and display it full screen.

A second method for reversing the effects is to leave the display turned off for a longer period.

The following measures can be taken to minimize the risk of image retention:
- Avoid static images, logos, text, etc.
- Use a –dynamic- screensaver when the display is not in use
- Periodically turn off the screen for 24-48 hours



Image retention caused by static (non-moving) images displayed for lengthy periods is not covered under Tipro warranty.