Sorry to say that burn-in is alive and well for LCD TVs. My Toshiba has thin dark lines where the black bars are aligned on each side of the screen, obviously from the times when there is no HD signal present. The lines are exactly where the normal screen width is located.
The lines only show up when an HD scene is showing a light blue, gray or sandy color. It's like someone has drawn thin lines where the black border ends and the picture begins on a normal 4:3 legacy picture. We only view legacy 4:3 pictures when the originating signal is is not broadcast in HD, usually around 50% of our viewing.
Toshiba service center is currently looking at it for repair under warranty.
Do LCD TVs Burn In?
Categories: Televisions and Projectors
What Is Burn In?
Burn in is one of the most commonly misunderstood concepts regarding television displays. Burn in is a phenomenon associated to television products, in which a static image left on the screen, over time, can permanently wear itself into the display. This issue is generally associated to phosphor based television displays like tubes, CRT rear projection, and plasma displays.
A common question asked is if LCD televisions are susceptible to burn in. The most common answer given to this question is no, LCDs are immune to burn in. However, this answer is somewhat of a half-truth.
The Truth About LCD and Burn In
It is a fact that LCD displays are immune to phosphor wear, simply because LCD televisions do not use phosphor to create a television image. Otherwise, it would be like saying an electric car can run out of gas.
However, LCD displays have certain characteristics that do not make them completely immune to static images. On LCD displays it's kindly referred to as "video memory." LCD panels use a complicated process of organizing liquid crystal molecules into a twisted or untwisted state, which allows polarized light to pass through the liquid crystal substrate. Over time, it is possible the liquid crystals can "get used to" the state of twist they are in, causing a static image, similar to phosphor burn-in, appear on the screen.
Some say that simply turning off the display for 24-48 hours eliminates the effect, while others have claimed the effect is permanent in extreme cases. Nonetheless, home users of LCD televisions have little to fear.
Why Video Memory Is Little Concern To LCD TVs
The nature of LCD products makes them extremely resilient to building up a video memory. In fact, you're far more likely to see this issue on LCD computer monitors. If, for example, the Windows or Macintosh desktop was left uninterrupted on a LCD display, with no screen saver for an extremely long period of time, impage persistence could become an issue and (possibly) be permanent.
LCD televisions, on the other hand, typically get enough image movement or power cycles that the buildup of video memory is highly unlikely. Leaving static images on an LCD display for a relatively short period of time will have no damaging effect to the display.
In other words, you'll only get video memory buildup on an LCD television if you try to do it on purpose or step well outside the norm when viewing static images.
What's outside the norm? Viewing a large amount of 4:3 programming on a widescreen display with static bars on the side can, as community members have pointed out in the comments area below, increase your risk of video memory or image persistence... even on LCD displays. While I still don't find it 'likely' that this commonly occurs, it's always prudent to limit viewing of static images whenever possible, so do yourself a favor and take advantage of the various formatting modes your television provides.
Better To Be Safe Than Sorry
Considering a large majority of television and movie content is optimized for widescreen displays these days, there's little need for the typical television watcher to concern themselves with video memory. It's just not likely under normal viewing conditions, but it never hurts to be safe than sorry. Follow these tips to ensure a video-memory-free experience with your LCD TV:
- Limit your viewing of 4:3 material on widescreen TV with static bars. Use the formatting modes on your TV to reformat 4:3 material to fit the 16:9 screen. Also, don't watch 1000 2.35:1 ratio DVD or Blu-Ray movies in a row.
- Be careful of channels that maintain a static, never moving, logo somewhere on the screen.
- Be careful when playing video games that contain a static graphics, like a life meter or HUD. Make sure you vary your gaming or watch other things between gaming sessions.
- Be careful of channels with stock tickers and other non-moving images
[Updated from original version; re-phrased to make it clear that while video memory is unlikely, it's not impossible. Thanks to WA6ATI for his comments.]
October 3, 2008 11:10 PM
January 25, 2009 12:55 PM
updated: January 25, 2009 10:19 PM
Respectfully, I do not agree with Matt Whitlock's final statement, There is no need for the television user to concern themselves with video memory because it's just not possible under normal viewing conditions.
I guess the operative word to consider here is "normal". What is normal? Not one vendor has stepped up and defined this variable. I have been in the service business for over 42 years and I have seen everything. What is normal in a lab environment is not the same, as John Q. Public understands it. We have seen hundreds of these LCD panels with this Image Persistence symptom so sever the panels require replacement.
This is nowhere near the tens of thousands of Projection TV CRTS, or Plasma TV's with image burn in. But to say that it is not possible for the LCD to have Image Persistence caused by a static graphical image, or running the set in the 4X3 mode for more than 50% of the time is unreasonable. It does happen and the consumer needs to be educated on how to prevent this.
Avoid static, stationary images on the screen d\for long periods of time.
Avoid running the TV in the 4X3 mode for more than 10% of the time.
Complain to your cable provider and broadcast stations to either move, eliminate, or otherwise alter their Logo that stays on the screen all the time.
Yes even these innocent logos from your friendly TV station, or Q V C Pricing logo have cost customers millions of $$ because of these logo burns.
As far as I know DLP was completely immune to Image Persistence or burn in.
Dennis
http://wa6ati.com
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January 26, 2009 5:01 PM
WA6ATI said: Respectfully, I do not agree with Matt Whitlock's final statement, There is no need for the television user to concern themselves with video memory because it's just not possible under normal viewing conditions. I guess the operative word to consider here is "normal". What is normal? Not one vendor has stepped up and defined this variable. I have been in the service business for over 42 years and I have seen everything. What is normal in a lab environment is not the same, as John Q. Public understands it. We have seen hundreds of these LCD panels with this Image Persistence symptom so sever the panels require replacement. This is nowhere near the tens of thousands of Projection TV CRTS, or Plasma TV's with image burn in. But to say that it is not possible for the LCD to have Image Persistence caused by a static graphical image, or running the set in the 4X3 mode for more than 50% of the time is unreasonable. It does happen and the consumer needs to be educated on how to prevent this. Avoid static, stationary images on the screen d\for long periods of time. Avoid running the TV in the 4X3 mode for more than 10% of the time. Complain to your cable provider and broadcast stations to either move, eliminate, or otherwise alter their Logo that stays on the screen all the time. Yes even these innocent logos from your friendly TV station, or Q V C Pricing logo have cost customers millions of $$ because of these logo burns. As far as I know DLP was completely immune to Image Persistence or burn in. Dennis http://wa6ati.com
After re-reading the artice (which I wrote a long time ago), it did come off as "it's impossible." While I still feel that this issue is highly unlikely, saying it's impossible simply wouldn't be true. I've updated and re-written sections to make it more accurate and useful to the reader thanks to your input.
Mind Over Matt'er - Technology musings, opinion, and more straight from TechLore's head geek.
May 12, 2009 8:35 AM
updated: May 12, 2009 8:47 AM
I'm horribly disappointed now knowing the "possible" problem of "burn in" with LCD TVs. There's a tremendous amount of 4:3 programming out there, and some of us don't like the "fat faces" one gets stretching the width of the image, or the cutoff of the top and bottom one gets in zoom mode. Given the scarcity and added expense of HD programming, this is unacceptable.
Rather than saying that image burn is not covered under warranty, like LG, the manufacturers could actually be proactive and do something about it. Maybe the manufacturers should vary the position of the 4:3 image left to right or up and down slowly, but continuously to avoid the static edges of the 4:3 image or letterbox bands for something not 16:9. I, for one, would not mind all that much that the side bars were uneven, or the letterbox bars were not the same size. Simple, simple programming, and a little ingenuity (and ownership of the problem) would be all it would take. Obviously, it is a problem the panel makers are trying desperately to hide.
May 12, 2009 11:15 AM
My TV repair guy was puzzled by the problem and said he had never seen it on any other TV before. He took it to a Toshiba repair center and they had to contact Toshiba. The official buzz word isn't burn-in. The new term for LCDs is persistance. They say it's temporary and to not let the 4:3 ratio pictures stay on the screen for a long time (did not specify what "long time" was). They also said they do not cover it under warranty, even though my warranty hadn't expired.
My experience is that it's not temporary although I don't notice it as much as I did before. Maybe because I know I just have to live with it.
The problem I have is that TV sales people use the no burn-in as a selling point when the manufacturers know there can be a problem - at least Toshiba knows.
I will never buy another Toshiba TV and I encourage those buying an LCD TV to stay away from Toshiba brand.
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