Samsung LS23CFUKFV-ZA - Manual (Page 81)

The best way to protect your monitor from Image retention is to set your PC or
System to operate a Screen Saver program when you are not using it.
Image retention may not occur when a LCD panel is operated under normal con-
ditions.
Normal conditions are defined as continuously changing video patterns. When the
LCD panel is operated for a long time with a fixed pattern (-over 12 hours-), there
may be slight difference in voltage between electrodes that work the liquid crystal
(LC) in a pixel. The voltage difference between electrodes increases with time,
forcing the liquid crystal to lean. When this occurs, the previous image may be seen
when the pattern is changed.
To prevent this, the accumulated voltage difference must be decreased.
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