OLED TVs have great picture quality; however, there are concerns about their long-term performance due to the possibility of permanent image retention, commonly referred to as burn-in.
Our previous 20 hours per day burn-in test ran for a little over two years, and the OLED TV has permanent image retention. That test was an extreme case, using patterns with a lot of static content.
Based on your feedback and comments, we bought six LG OLED C7, which played real, non-altered content. It gives a more realistic, real-world example of what to expect depending on how you usually use your TV.
This test ended in 2019, as we feel that we now have a good understanding of what types of content are likely to cause burn-in. However, we still haven't addressed the issue of longevity in general, and we don't know if newer OLED panels are still as likely to experience burn-in. To that end, we've decided to start a new accelerated longevity test to better understand how long new TVs should last and what are the most common points of failure. Although burn-in isn't the main goal of this test, we're hoping to better understand how newer OLED panels compare to the older generation of OLEDs. It's generally accepted that burn-in isn't as much of an issue as it used to be, but it's unclear just how much better the newer OLED TVs are. With new panels, new heatsinks, and even brand-new panel types like QD-OLED, there are a lot of unknowns.
Update 05/31/2019: The TVs have been running for over 9000 hours (around five years at 5 hours every day). Uniformity issues have developed on the TVs displaying Football and FIFA 18 and are starting to develop on the TV displaying Live NBC. Our stance remains the same: we don't expect most people who watch varied content without static areas to experience burn-in issues with an OLED TV.
Update 11/05/2018: After more than 5000 hours, there has been no appreciable change to the brightness or color gamut of these TVs. Long periods of static content have resulted in some permanent burn-in (see the CNN TVs); however, the other TVs with more varied content don't yet have noticeable uniformity issues on normal content. As a result, we don't expect most people who watch varied content without static areas to experience burn-in issues with an OLED TV. Those who display the same static content over long periods should consider the risk of burn-in, though (like those who watch lots of news, use the TV as a PC monitor, or play the same game with a bright static HUD). Those concerned about the risk of burn-in should go with an LCD TV for peace of mind.
Note that we expect burn-in to depend on a few factors:
The total duration of static content. LG has told us that they expect it to be cumulative, so static content, which is present for 30 minutes twice a day, is equivalent to one hour of static content once per day.
The colors of the static areas. We found that in our 20/7 Burn-In Test, the red sub-pixel is the fastest to degrade, followed by blue and then green.
To see how the results at this 5000-hour point compare to your usage, divide 5000 by the number of hours you watch each type of content per day to find the number of days. For example, someone who plays Call of Duty or another video game without bright static areas for two hours per day may expect similar results after about 2500 days of usage. It corresponds to about seven years.
The goal of the test is to provide an idea of the usage time of a 2017 OLED TV before burn-in becomes apparent, which will depend on your usage. To do so, we replicated five different real-world conditions in an accelerated aging test. We also independently tested two different brightness ('OLED Light') settings with the same content to see the impact.
The TVs are all controlled by a microcontroller to repeat a five-hour on and one-hour off-cycle four times per day.
The 'Screen Shift' option was enabled on all TVs, and 'Pixel Refresher' was performed before each set of measurements taken on each TV.
They all played real content (not test patterns) from live cable TV sources, video game clips, or recorded sports. The brightness of all TVs (except the one identified below) was set to 200 nits on a checkerboard pattern, with the content described below.
The settings remained at their default values in the 'isf Dark Room' picture mode, with only the 'OLED Light' adjusted. The specific value depends between units but is typically between 59 and 63 to reach our target of 200 nits. The maximum brightness TV had 'OLED Light' at 100.
CNN was played live on the TV through a cable feed - as a result, this includes all regular broadcast content, including commercials. CNN is a widely watched network news channel, and we have also received concerns regarding this channel specifically. This test is considered a control, with the 'OLED Light' set to a brightness of 200 nits.
As above, live CNN was played on the TV through a cable feed. For this TV, the 'OLED Light' is set to maximum, corresponding to a brightness of 380 nits on our checkerboard pattern. It's to show the relationship between burn-in rate and 'OLED Light' with the same content and over the same period.
Many pre-recorded football games were displayed on this TV to represent the usage of someone interested in a particular sport and will watch it regardless of the channel. It includes content from a variety of channels and with different teams, so overlays are located in different areas, and team colors change. It includes many games to avoid too much repetition.
This test is informative for people who watch a lot of general TV since NBC shows a variety of movies, TV shows, sports, and news. The source was a live cable feed and should be representative of a range of general TV content.
The goal of the content on this TV is to investigate the effect of a 'high risk' video game - one which has some bright, static areas which remain very consistent. We have received the most concerns about FIFA 18, so many hours of gameplay footage were used to show typical usage, including many different teams and a mix of menus and gameplay without much repeating.
The gameplay footage on this TV is to represent a relatively 'low risk' video game. It only has small areas which are static and an overall dim image without too many bright colors. We haven't received any reports of burn-in for this game yet, so consider it a baseline for a low-risk game.
A NodeMCU microcontroller is used to control each TV at all times. It has 6 IR LEDs, which are connected to the IR receiver of each TV, to power them all on and off at specific intervals. The status and toggle times are logged via WiFi to a server to verify accurate timing.
There are a few different 'pixel refresher' functions that run on LG OLED TVs. An 'automatic' pixel refresh runs when the TV is turned off after four hours of cumulative usage. This requires the power to be connected, and LG has told us that this takes between 7 and 10 minutes to complete. As a result, this pixel refresh is automatically run at each power cycle of our test (4 times per day).
There is also a 'manual' pixel refresher function which is toggled through the settings menu. This may take an hour to complete, and we manually run this before taking each set of photos (as described above).
The automatic backlight limiter reduces the brightness of the screen to prevent it from drawing too much power. It occurs when there are large bright areas, and it's why our 100% window measurement of OLED TVs is significantly lower than smaller window sizes (see here). It doesn't mean that increasing the 'OLED Light' will result in a dimmer image. The overall image is still brighter with a higher 'OLED Light' setting.
Every two weeks we will take photos of 50% gray, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta, and 100% yellow patterns and post the photos here. Every two months we will measure the color gamut and HDR peak brightness of each TV.
The goal of this test is to provide an idea of an OLED TV's lifespan before burn-in becomes visible when watching real world content. This article will be updated every two weeks with the latest results from our real-world test, and how it should impact your buying decisions depending on your own specific usage.