Lies or truths: plasma TV screen burn-in problem tested on real machines

Plasma TVs have the advantages of excellent dynamic display and true color reproduction. However, no matter how good the picture quality of plasma TVs is, the problem of "screen burn-in" will always bother everyone. So whether the plasma TV screen burn-in phenomenon is outdated news, fabricated by merchants, or excessive worry of netizens, there is no clear answer. Now, the home appliance channel evaluation room will conduct a 24-hour test on plasma TVs to give everyone the truth about "screen burn-in".

Lie or truth? Plasma TV screen burn-in problem tested on real machine

What is plasma screen burn-in?

Plasma TVs have the advantages of excellent dynamic image display and true color reproduction. However, the problem of plasma "burn-in" is an important reason that prevents people from choosing to buy it. So what is the problem of "burn-in" that we often hear about? First of all, "burn-in" does not mean that the screen is burned out, but due to the display principle of plasma, if a static image is kept on the screen for a long time, traces of the static image will be left on the screen. It can be seen that burn-in should be defined as "afterimage" or "afterimage".

Plasma "burn-in" refers to permanent pixel marks left on the screen

Some friends may think that they do not have many static images in their daily use. However, the channel logos when watching TV, the status and navigation bars when playing games, and the static icons and status bars in the computer interface are all unavoidable situations in the daily use of flat-screen TVs.

Common still images

There are also quite a lot of still image elements on the computer desktop

Plasma panel principle

The plasma panel uses plasma tubes as light-emitting elements. Each plasma tube on the screen corresponds to a pixel. The screen uses glass as the substrate. The substrates are spaced a certain distance apart and sealed airtightly around to form discharge spaces. The discharge space is filled with mixed inert gases such as neon and xenon as the working medium. When voltage is applied to the electrodes, the mixed gas in the discharge space undergoes plasma discharge. The gas plasma discharge generates ultraviolet rays, which excite the fluorescent screen, which emits visible light and displays images.

Plasma panel principle

Plasma panel principle

Has the screen burn-in issue been resolved?

Although the "burn-in" problem is unavoidable according to the display principle of plasma, there are many claims on the Internet that plasma has greatly improved this problem. The main reasons are: First, the phosphor and other materials in plasma screens have been updated, which means that the afterimage after "burn-in" will not exist forever, but become an "image retention" problem that disappears after displaying other images for a period of time.

The scroll bar option can also reduce the ghosting problem

The second point is that plasma manufacturers have invented a variety of built-in programs to avoid screen burn-in, such as "pixel drift", "edge brightness adjustment" and timed "anti-screen burn-in program", etc. These functions mainly avoid the "screen burn-in" problem by reducing the time each pixel displays a static image, which is a limited improvement compared to the first point.

Plasma TV manuals still warn against displaying still images for long periods of time

Note: Screen burn-in is not covered by the warranty.

Purpose of this test

But is it true that plasma TVs are no longer troubled by the "burn-in" problem as everyone says? There is no clear answer to this question so far, so this time our evaluation room is going to conduct a detailed test on a plasma TV on the "burn-in" problem.

Test method: Brutal long-term static image test

The test method is not complicated. We will make a plasma TV (Panasonic GT31, mid-to-high-end) display a still image for 24 hours and increase the contrast of the plasma TV to test whether the TV has screen burn-in problem. I believe that the 24-hour test time is more representative because few people watch the same TV program or game for more than 24 hours.

It should be pointed out that the test environment and TV settings were extreme, because in the first test, we did not find obvious burn-in effects after 100 hours of regular static image testing. According to the cause investigation, we found that this was due to the brightness and contrast of the picture. According to online information, we adjusted the TV to the extreme state in order to detect whether the "burn-in" problem still exists and whether the new technology can completely eliminate the "burn-in" phenomenon.

In addition, this evaluation can be seen as a situation where the TV is adjusted to an extreme state, and someone at home falls asleep or goes out with the TV on, the TV program ends, and a circular fixed image appears. Readers are welcome to apply this situation to themselves.

If "image persistence" occurs, we will make the plasma TV run a high-definition video for a long time to see whether the persistence is a short-term "image retention" or is difficult to remove.

Plasma "burn-in" test preparation

1. Introduction of test equipment

The target device for this test is the Panasonic TH-P46GT31C plasma TV. Since it is a mid-to-high-end model of the Panasonic brand, it is quite representative for measuring the burn-in problem of current plasma TVs.

Before starting the test, we will turn off the automatic standby function, screen saver and other energy-saving functions in the plasma TV to ensure that the TV can remain on for a long time.

Turn off the automatic standby function

At the same time, we retain the "pixel drift" and "edge brightness adjustment" options in the TV. These functions are the anti-burn-in programs mentioned earlier, and we can verify whether they are really useful later.

Turn on the preset anti-burn-in option

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At the same time, the Sony PS3 game console is used as the signal output. We also need to turn off the automatic shutdown option in the PS3 to ensure that the machine can operate for a long time.

Keep your PS3 running for 24 hours

2. Test Method

Since the burn-in problem of plasma is caused by displaying static images for a long time, we chose to display a color card on the TV, so that we can better understand which colors the burn-in problem is more likely to occur. At the same time, we adjusted the display mode of plasma to vivid, that is, the state of maximum contrast, because the "burn-in" problem is closely related to contrast, and this extreme state can make us have a clearer judgment on the possible burn-in problem of plasma.

At this point, the preparation process for the test is over, and all we have to do next is wait patiently for about 24 hours.

If you want to know the results of screen burn-in, please read the following patiently.

Screen status after 24 hours

The results of the "burn-in" problem can be seen after the plasma TV keeps displaying a static image for about 24 hours.

Looking at the plasma TV display in the original image, there is no difference. No trace of "afterimage" can be seen on the screen when the screen is turned off or displayed in a completely black picture.

The "image sticking" phenomenon occurs!

However, when switching to a completely white screen, obvious color blocks appear on the screen. Obviously, these are "image afterimages", but whether they are permanent or not is still unclear.

Afterimage phenomenon occurs

Afterimage Details

Only when a bright background is displayed can we see obvious blocky traces.

When the displayed images are more complex, it is actually difficult to detect these so-called "image sticking" problems, which means that under normal circumstances, the sticking does not have a serious impact on the viewing experience of the TV.

Although it has no obvious impact on general pictures, I believe many friends would not be so willing if there is a risk of afterimages.

Analysis of the "Image Afterimage" phenomenon

Under a completely white background, the author said that the afterimage phenomenon can be clearly observed, but when shooting with a camera, these traces are difficult to detect. Therefore, for the afterimage picture, the author slightly adjusted the curve in Photoshop to ensure that the actual effect is similar to the picture display. By comparing with the original picture, it can be seen that the afterimage problem is mainly caused by the high contrast. The lighter the color and the higher the brightness of the color block, the darker the trace formed, and the afterimage is the inverse color of the color block, just like a film negative.

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It is important to emphasize here that because "Edge Brightness Adjustment" is turned on, when displaying a 4:3 image, the colors of the two black edges on the left and right are less obvious than the afterimage of the original black border part of the picture, which shows that this anti-burn-in program still has a certain effect.

Less afterimages from black edges

However, so far, I can only say that plasma TVs will have a certain amount of "image retention" when displaying high contrast for a long time. As for whether it is a permanent "screen burn-in" problem, we will let the TV accept two methods, namely turning it off and displaying a continuous high-definition video, to see whether these afterimages will disappear or weaken afterwards.

Read on to learn whether image retention is a temporary phenomenon or permanent.

Test results of eliminating “image sticking”

After the image sticking appeared, I first turned off the plasma TV for about 12 hours. After turning it on, I could still see obvious image sticking, which at least shows that turning off the TV cannot quickly alleviate the image sticking problem. So the next step is to test the dynamic image playback for up to 24 hours. If the effect is not obvious, we will further extend the test time.

After playing the HD video for 24 hours, we switched the picture to all white again and found that the "image afterimage" still existed, but the afterimage phenomenon had improved slightly (there is a certain difference between the photo and the actual perception, and the actual difference is smaller than the photo). From the screen shots taken two days apart, the image afterimage has improved slightly, but the degree is still not obvious.

White screen image 24 hours ago

White screen after 24 hours of video playback

Since the test time was not long enough, we continued to extend the test time. After playing the video continuously for 48 hours, we shot a full white background again. Although the afterimage still exists, it is much lighter than before, but we will continue to test it in the future.

White screen after 48 hours

It seems that if such a residual image problem occurs, the plasma TV cannot recover quickly in a short period of time. However, there are also claims on the Internet that the phosphor of a plasma TV will show obvious attenuation within 300 hours, so the image residual image we see is actually caused by the uneven attenuation of the phosphor. Therefore, it takes a long time to recover from the "image residual image" (hundreds of hours). For this statement, the author feels that it is relatively credible. After all, after 48 hours, the residual image phenomenon has recovered to a certain extent. But let me tell you here that this test is still in progress, and there will be subsequent updates in a week. If the residual image of the plasma has improved significantly by then, then this statement can be proved to be credible.

Plasma "burn-in" test conclusion

Conclusion of this test

Editor's summary: Based on the current test, we know that the saying of "burn-in" of plasma TVs is indeed real, and in the case of high-contrast static images, plasma TVs are indeed prone to image retention problems, and the time it takes for the image retention to disappear is not as some rumors on the Internet say, that it may disappear within 24 hours, but may take a longer time. Therefore, if the "afterimage" problem occurs, it will still affect the picture quality of the TV. If the static picture exceeds the time of this test, the consequences may be more serious, leaving irreversible traces.

Therefore, we would like to remind all users that if you buy a plasma TV, you should avoid letting the screen display static images for a long time. The usage methods that are prone to this problem include the progress bar when playing games, the TV station logo, and the operation of the computer. If users often continue the above operations for a long time, they need to adjust the screen within four hours to avoid the problem of image retention. Here, the author would also like to remind users that if they need to connect the TV to the computer for a long time, it is still not recommended to choose a plasma TV.

Fortunately, if you are just worried that you will forget to turn off the TV and cause screen burn-in, you only need to turn on the automatic standby function or screen saver function in the settings. The TV will then automatically go into standby after a period of inactivity, thus avoiding the problem of screen burn-in.