0 comments | Thursday, August 23, 2007

If you've been researching HDTVs, you've heard about a nasty little problem, unique to plasma and CRT sets, called burn-in. That's when your $4000 plasma screen gets imprinted with the ghostly image of a TV channel's logo or the outline of a letterbox because certain parts of the screen have aged faster than the rest. But if it's such a big deal, why do people keep buying expensive plasma HDTVs? Is burn-in really worth worrying about?

Burn-In Susceptibility in Modern Plasma HDTVs
The HDTV industry is very competitive these days, and plasma manufacturers are really starting to feel competition from the LCD industry. So, you can bet they're doing everything they can to eliminate burn-in. Screen technology has improved to the point where proper use of the TV (starting with a detailed break-in process) will not cause a problem, but careless use just might. And many of the new plasma HDTVs, like the Samsung HPT5064, have a "screen burn protection mode" built into the TV to repair mild damage.

Image Retention vs. Burn-In
Image retention is a common effect that you might have seen after turning off a CRT television at night: the last image to appear on the screen stays there for a while after the TV is off, then fades away slowly. This is caused by a charge build-up in the phosphors (the glowing picture elements in the screen), and will go away after the display has been powered off for a little while.

Burn-in, on the other hand, is permanent. Since it is caused by uneven aging of the screen phosphors, the "burned" image will persist forever, like a tattoo. It can be caused by spending a lot of time watching stuff in a 4:3 (non-widescreen) aspect ratio, watching a news channel with a stationary "news ticker", or playing a game with stationary screen elements. Just as a tattoo can be removed with a great deal of effort, there are ways to fix a burned-in screen. But an ounce of prevention is worth a pound of cure: follow a break-in procedure when the set is new.

The Break-In Procedure
If you would rather be safe than sorry, you'll need to go through a break-in process when the TV is new. In 2004, Panasonic commissioned a detailed look into the problem and came up with some guidelines for new plasma owners:

In the first hundred hours:

  • Make sure the display is in a viewing mode (aspect ratio) that completely fills the screen (there are often three or more settings from which to choose). The panel is shipped in this condition, in what is called the "Just" mode.
  • Turn down the contrast to 50% or less.
  • Briefly engage the 4:3 mode to confirm that the side bars are set to mid-gray to minimize the chance of burn-in.
  • Return the set to a "full screen" (Just, Zoom, Full) position during the first hundred hours of use.
  • During the first hundred hours of use, don't view the same channel for extended periods. This should prevent channel logos and other fixed images from being retained.
  • Avoid any static images (video games, computer images, DVD title screens, etc.) during the hundred-hour break-in.

After the hundred hour break-in period, during the next nine hundred hours:

  • Continue to retain the contrast setting at 50% or less.
  • Limit the use of 4:3 aspect ratio mode to 15% of viewing time.
  • Limit the use of static images (computer, video games, etc.) to less than 10% of viewing time.
  • After one thousand viewing hours, panels are much less likely to experience image burn-in.

The Bottom Line
HDTV experts agree now that burn-in is an overstated problem. Complaints now come from a much smaller percentage of owners than they used to. Buying a late model plasma HDTV, using a break-in procedure, and avoiding certain viewing habits should reduce the chance of damage to just about zero.

About the Author

Tom Webster writes for FlatHDTV.net and the FlatHDTV Blog FlatHDTV.net is an online guide to the HDTV revolution.

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