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Avoiding image persistence on Apple displays
In-plane switching (IPS) technology is used in today's most advanced displays, including the Apple Cinema and Thunderbolt Displays, as well as the displays built in to iMac and Macbook Pro with Retina display computers. IPS technology enhances the viewing experience by providing full 178-degree viewing angles in all directions. This makes IPS displays ideal for observing content with multiple people, and provides pristine viewing characteristics for image, print, and video production workflows.
On an IPS display, when an image such as a login window is left on screen for a long period of time, you may temporarily see a faint remnant of the image even after a new image replaces it. This is referred to as "persistence," "image retention," or "ghosting." This is normal behavior for an IPS display, and the faint image will disappear over time.
You can prevent image persistence by using the display sleep feature to turn off the display when it is not in use. You can also use a screen saver to make sure that a static image isn't on the display for long periods of time. Both of these features are on by default in Mac OS X, but you can adjust the settings as needed.
To prevent image persistence, enable the display sleep feature:
From the Apple () menu, choose System Preferences, and then click Energy Saver.
Click the Battery tab (if using a notebook).
Set the "Display sleep" slider to a brief interval of time (such as 15 minutes).
Click the Power Adapter tab and make the same change (if using a notebook).
If you see a persistent image on your screen, you can use the screen saver to eliminate it:
From the Apple () menu, choose System Preferences, and then click "Desktop & Screen Saver."
Click the Screen Saver tab.
Choose a screen saver.
Set the "Start screen saver" time to be shorter than the "Display sleep" and "Computer sleep" settings in the Energy Saver pane of System Preferences.
To clear the persistent image, allow the screen saver to run for approximately as long as the image was being displayed.