Plasma

Test Procedure

The issue of image retention, otherwise popularly known as “burn-in”, is of concern to any potential buyer of a plasma TV. To test for image retention and differential phosphor aging, three eight-hour cycles were operated. All plasmas were set to their “normal”, “daylight”, or “standard” operating mode for each cycle.

• Cycle 1 Test

• Cycle 2 Test

• Cycle 3 Test

Conclusions

Only one plasma TV showed any easilyseen evidence of image retention when operated in standard viewing modes for three consecutive eight-hour periods displaying contrast, color bar, and static TV images. A second plasma TV showed a mild ghost image that was discernable even after a 24-hour shutdown period. The remaining three plasma TVs had little or no evidence of any ghost images after the 24-hour static image test.

From this test, image retention appears not to be caused by phosphor burn-in. Rather, it appears to be an accumulated electrical charge within pixel walls. A full white image was displayed for a few hours on the two plasma TVs that showed residual images, after which the residual images disappeared completely. Had the phosphors aged sufficiently, this procedure would not have been enough to clear up the problem.

This points to the possibility of a residual electrical charge accumulating within the individual pixel walls, much like a capacitor. The all-white test pattern apparently cleared this charge.

Consumer Perspective

Image burn-in (differential phosphor aging) should not be a problem for any plasma TV that is operated in a standard or daytime picture mode, viewing a normal mix of video content. For video gaming, select a picture setting that reduces image brightness and contrast accordingly, as recommended by the owner’s manual.