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Background: What is the risk of burn-in with OLED?

You have known to the term burn-in with OLED. This article will explain you all about the phenomenon, its consequences, and solutions.

OLED televisions offer fantastic picture quality, but the question remains about burn-in. Is ‘burn-in’ a problem, is it temporary or permanent and how can you best avoid it?

re there certain viewers who prefer LCD? We try to answer all these questions.

OLED: a refresher

How does OLED work again? OLED stands for Organic LED. In essence, an OLED panel consists of a glass plate on which are mounted the transistors that switch each pixel on or off (the TFT layer), above it is a white OLED layer and above it is a color filter that determines the color of the sub-pixels. OLED screens use a four sub pixel structure, in addition to the classic red, green and blue sub pixel, there is also a white one. The main feature of OLED is that each sub-pixel itself emits light. When off, it is completely black regardless of the condition of its closest neighbors. OLED, for example, has a fantastic contrast. Because it is an emissive technology (each pixel itself emits light), the screen also has a very wide viewing angle. If you want a complete overview of how OLED works correctly again, we refer to this background article .

The main difference with LCD also deserves a brief explanation. An LCD TV uses a backlight to make its light. Each sub-pixel determines whether or not that light is transmitted (that is why we speak of a transmissive technology). But because the LCD panel cannot completely block the light, the black level is not perfect. This is improved by using different background lighting and smart dimming technology. For an overview of the operation of LCD and the backlight, read more in our article about backlighting .

What is burn-in?

To begin with, we must distinguish between temporary burn-in and permanent burn-in. Temporary phenomena are also referred to by the term ‘image retention’, while permanent problems are more often referred to as ‘burn-in’. However, these are not hard rules, so keep that in mind when reading other articles.

Image retention

OLED has some problems with temporary burn-in, we sometimes see that when we show a white window on a black screen in HDR during our tests. That test window represents a very extreme situation that is also on the screen for quite a long time (often several minutes). When we then show a black screen, a remnant of the white window can often be seen faintly. That effect usually disappears after a few minutes. In normal use, this problem is avoided by a number of measures in the screen (more on that below).

Burn-in

Burn-in can best be viewed as non-homogeneous wear of the subpixels. When parts of the picture (channel logos, game interfaces, etc.) remain static in the picture for a long time, the subpixels that are on will wear out in that place faster than others, just because they are permanently on.

After a long time you can see a permanent ‘ghost image’ of the logo or interface. You cannot get rid of the burned-in logo, even with the built-in security measures. The problem of burn-in is real, as we will see later, but it would be rather exceptional under normal circumstances.

Official positions

We asked the TV manufacturers that offer OLED for an official position on burn-in. We see that the existence of burn-in is confirmed, but the risk is estimated to be very low.

LG : “OLED is a self-emissive technology that offers many advantages in terms of image quality and performance. As with any self-emissive technology, OLED TVs may experience temporary image retention under certain conditions. However, permanent image retention, or burn-in, are rather rare under normal use. With our 5th generation OLED panels, LG remains a leader in the large TV market segment. These screens undergo strict quality controls to ensure durability, reliability and customer satisfaction.

As a result, today there are millions of satisfied LG OLED users who have never reported an issue of permanent image retention.

In addition to strict quality controls, LG continues to develop technologies to prevent image retention. Examples are the pixel refresher, which is automatically activated to keep LG OLED TVs in the best conditions. ”

Philips : “Due to the organic nature of the OLEDs, burn-in of images is possible in exceptional cases (eg with a still image for hours or days). However, this is avoided 100% on Philips TVs by a number of smart solutions. ”

Sony : “In general, image retention only occurs when a certain pattern is displayed on the screen for a long period of time. To avoid this rare effect, Sony BRAVIA OLED TVs continuously analyze the image patterns via the X1 Extreme processor / X1 Ultimate processor. In addition, Sony uses “Pixel Shift” technology to prevent certain pixels from being illuminated for too long. It is very exceptional for a Sony BRAVIA OLED TV that image retention occurs with normal use and observing the manual supplied. ”

Panasonic : “As a fact, latest generation OLED panels have much endurance against burn-in than PDP and old OLED. Thus, it would not happen in the typical home use. Furthermore, our OLED TVs have pixel refreshing function which runs in standby mode (background) when long-time use is detected. ”

OLED and burn-in: a tough test

Because burn-in is a phenomenon that you can only detect after a long time, it is not easy to test it. However, rtings’ colleagues have drawn up a lengthy line-up to demonstrate that burn-in does exist.

In their first version of the test, they placed two LCD televisions (one with VA panel and one with IPS panel) next to an OLED TV. The screens are on for 20 hours a day and off 4 hours a day, and run a 5.5 hour test video in a continuous loop. The video material is varied, but has a logo in the four corners with different brightnesses and which is present on the screen for different periods of time. One logo is displayed permanently and with full clarity, as a ‘torture test’.

Twenty hours of continuous watching TV a day, always watching the same content and always with the same logos on the screen may not be a realistic test scenario, but you can draw conclusions from it. OLED is sensitive to burn-in. The first forms of burn-in appeared after only four weeks, and after 7 weeks (980 hours) the four logos were visible.

After a year (more than 7000 hours), the conclusions were that the LCD TVs showed no signs of burn-in. The effect on the OLED TV was clear. The red sub pixels appear to deteriorate fastest, followed by green and blue. The black bars above and below a film do not affect the uniformity of the screen.

You can find the full explanation and results of the test here .

A realistic test

Because this first test was absolutely not a realistic scenario, rtings started a second test. This time with six LG C7 screens. All screens are on for five hours, then off for one hour, four times a day. The footage is a good sample of real TV usage.

  • Two screens show live CNN, one of which is at maximum brightness (380 nits), the other acts as a control and is set at 200 nits. CNN serves as an example for those who watch a lot of news, the channel also always has a logo and news bar on screen.
  • A screen shows live NBC, and serves as a test for a varied selection: sports, TV shows and news.
  • A screen shows pre-recorded sports broadcasts. The content comes from different channels and teams so that colors and logos differ. By using a wide range of matches, there is little repetition.
  • Two screens show gaming content. One for FIFA 18, a risk game because it has a lot of bright and static screen elements. Here too a varied series of teams and matches have been chosen. The last screen shows Call of Duty.

The test has now run for more than 4,000 hours and there are no burn-in problems on the sports broadcasts, live NBC and Call of Duty television. The devices that show CNN, on the other hand, are clearly burned in. (first visible issues after 2,000 hours).

This also confirms that red screen elements cause burn-in the fastest. The device that played FIFA 18 has some slight uniformity problems after 4,000 hours.

You can read the full results and setup of this test here .

What is the risk of burn-in?

Ultimately, the risk of burn-in with normal use appears to be very limited. Normal use in this case means a varied viewing pattern. Gamers who play the same game for a year, and do so for many hours a day, run a risk (although that depends on the game, as the test shows, you run no or very limited risk with some games). Those who leave their TV on day in, day out on the same channel that also continuously keeps certain picture elements in the picture statically, should not opt ​​for an OLED screen. Although you may wonder whether this still qualifies as a normal consumer. (Panasonic, for example, emphasized that OLED TV is intended for ‘household centers’). We can reassure frantic film viewers, the black bars above and below the film do not seem to cause burn-in.

How do you limit the risks?

Once burn-in is a fact, you can no longer get rid of it. So prevention is the message, but how do you do that?

The first and most important guideline is to use a varied viewing pattern. That sounds like a serious limitation, but looking at the realistic test, it is actually not so bad. It sounds fairer to say that only extreme viewing patterns pose a risk.

Manufacturers build in all kinds of mechanisms to prevent burn-in. Then leave it activated. (in many cases you cannot even deactivate them). This is the list that Philips provided to us, but which is also valid with other manufacturers:

  • Pixel shift: the entire image will discreetly shift a few pixels so that the OLEDs take on a different color. For example, the image shifts a maximum of 32 pixels (of the> 8 million) to the left or right and 16 lines up or down at 1 pixel or line per 80 seconds, so not noticeable to the customer. Also (channel) logos are automatically detected and displayed in this way. This mechanism is always activated when the TV is on and cannot be switched off.
  • Still image detection: This is also always activated when the TV is on and cannot be switched off. With a still image for more than a minute, the contrast will decrease very gradually.
  • Screen saver: this is also activated whenever the TV is on and cannot be switched off. When a menu, either from the TV settings, Android TV or an app, is displayed for more than 2 minutes without any action from the user, the screen saver will activate with a Philips logo moving back and forth across a black screen.
  • Removal of residual images: the OLEDs are completely reset. This process happens automatically in the background (customer will not notice) when the TV goes into standby mode after more than 4 hours of play. In exceptional cases, for example, when the TV is repeatedly turned off to full power instead of standby, the process cannot start and the customer will see a message at the next TV start-up asking for the process now. or later. If there is no response within 2 minutes, the TV will automatically go to standby mode to start the process. If ‘later’ is chosen, for example because it is just an exciting end to a film, he / she will be offered the message again at the next viewing session. This function can also be started manually via the TV menu.

It is therefore recommended to switch off your OLED TV with the remote (so that it is in standby). Avoid unplugging and do not use a home automation switch to turn off the power completely. After all, this prevents the ‘refresh’ process from being performed automatically.

Checking and intervening now and then is an option if you really want to avoid all risks. Show a uniform gray image and see if you detect problems. If this is the case, activate the removal of residual images yourself via the menus of the television. This function can be found at the following place:

LG: Picture / OLED Panel Settings / Pixel Refresher
Philips: Picture / Advanced / Delete Residual Images
Sony: Picture & Display / Expert Panel Settings / Panel Refresh
Panasonic: Picture / Picture Settings / Screen Care

Do not use that function too regularly (for example, certainly not weekly), you will accelerate the aging of the panel. The built-in refresh that happens when you put the device in standby should suffice. Sony even recommends in its manual to do this no more than once a year.

What about warranty?

We will be straight to the point: burn-in is not covered by the warranty. Again, we asked the manufacturers for feedback.

Philips : “The expected lifespan of an OLED TV is the same as that of an LED TV. Since our OLED TVs are equipped with different mechanisms to avoid burn-in 100%, burn-in is not covered by the warranty. The only way burn-in could occur with our TVs is that the TV is never put into standby mode and that the customer has interrupted the process to remove residual images several times. If a case of burn-in is reported, it is examined together with the customer whether it still helps to manually remove the residual images, one of the mechanisms to combat burn-in. ”

LG : “The lifespan for an OLED TV is variable and depends on the use, but with normal TV use the lifespan is the same as that of LCD TVs. Cases of burn-in are very rare and are considered on a case-by-case basis. ”

Sony : “In this particular case, if the automatic or manual screen refresh is not effective, we recommend that you contact an authorized Sony service center or Sony authorized retailer. The problem is diagnosed in consultation with the consumer. If necessary, Sony offers a suitable solution for the consumer. ”

Panasonic : “The burn-in effect is not included under the warranty. Commercially, the cause is examined on a case-by-case basis and a proposal is made in function, even after the warranty period of 2 years. ”

Conclusion

Image retention (temporary) and burn-in (permanent) are existing problems on OLED. If you temporarily see an ‘afterimage’ that disappears after a few minutes, then you do not have to worry. This kind of ‘image retention’ does not create any problems. However, OLED can suffer from permanent burn-in. Based on the current long-term tests, the risk appears to be rather limited. In any case, keep all anti-burn-in measures activated (pixel shifter, screen saver, and pixel refresh on standby), and never switch off your OLED TV completely (always put it on standby). An average viewer who watches a varied range of channels and content does not have to worry much. If you look at content for a very long time that also keeps static elements in the picture, there is a possibility of burning in.

 

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