Not burn-in: Scary OLED TV image retention may stem from “buggy” feature

Image retention is scary to see on your OLED TV but often easy to eliminate. Many modern OLED TVs subtly work their own magic when you're not watching in order to remove the problem, as RTINGS demonstrated in a video released Friday. However, TV vendors aren't all doing perfect jobs at implementing OLED screens' compensation cycles.

 

Temporary image retention differs from permanent image retention, aka burn-in, in that it points to a change in the panel's thin-film transistor (TFT) layer, rather than degradation of the OLED layer. Untreated temporary image retention doesn't lead to burn-in, a Sony spokesperson confirmed to me, but anyone looking at a screen suffering from image persistence will want to eradicate the sticky images, fast.

 

These temporary artifacts can be the result of heat affecting the amount of light emitted by the OLED pixels and can happen within minutes of usage. But letting the TV cool down by turning it off usually fixes this.

 

But the other type of temporary image retention, TFT threshold voltage shift, "is a lot more dependent on the TV's internal functions and downtime," a RTINGS spokesperson said in Friday's video. RTINGS, which is currently running a high-use longevity test of 100 TVs, explained that the "characteristics" of an OLED TV's TFT layer can sometimes "drift," causing temporary image sticking.

 

"It can take as little as one hour of on-time running with static elements for this type of image retention to set in, but over time the image retention accumulates," RTINGS' spokesperson said.

 

Like the other type of temporary image persistence mentioned, this is normal to see on an OLED TV. And it can be cleared with a short compensation cycle.

Fixing temporary image retention

Thankfully, today's OLED TVs can run short compensation cycles that address changes to the TFT's voltage without interrupting the user, since the cycles are set to automatically run when the TV is off and has been used for a certain number of cumulative hours. Known by various names, including Pixel Refresh and Screen Optimization, depending on the TV vendor, they usually last under 10 minutes and "detect and compensate for changes in the TFT layer's electrical characteristics and return it to a baseline state," as per RTINGS.

 

RTINGS used a 42-inch Sony A90K, a quantum dot OLED (QD-OLED)TV from 2021, to illustrate a short compensation cycle clearing temporary image retention. The A90K reportedly suffered from temporary image retention after RTINGS put it through a "torture test," that required it to run a CNN stream with a static overlay of the RTINGS logo and colourful squares for 120 hours.

 

This is a good time to remind everyone that RTINGS is using extreme testing conditions. RTINGS' typical longevity test aims to simulate 10 years' of use in two years, but the A90K's testing here is even more intense. It's unlikely a normal user would push a TV this hard.

 

As you can see in the screenshot from RTINGS' video below, most of the visual artifacts on the A90K went away after one short compensation cycle run.

 

The next screenshot video also helps demonstrate how effective a short compensation cycle can be at removing image sticking. It shows Sony's 2021 A80J white OLED (WOLED) TV with 50 percent gray slides. After eight months, RTINGS ran a short compensation cycle on the TV, and the difference is noticeable.

 

Inconsistencies

Pixel refreshes that are run while the TV is off can remove sticky images and save users much concern. However, RTINGS' testing spotted inconsistencies around when short compensation cycles auto-run among TVs from the same brand and even among TVs that are the same model. The publication's rep said RTINGS "found a lot of buggy implementations, which can result in more image retention appearing on your screen."

 

Sony has said OLED TV short compensation cycles run after various amounts of usage, as RTINGS pointed out. When contacted via email, the company reportedly told RTINGS that its TVs can automatically run short compensation cycles after four hours of cumulative usage. Online, you can find support pages pointing to "a few hours" as well as "six hours or more," depending on where you look.

 

RTINGS claimed that its Sony A80J and A90J (WOLED) TVs weren't running any short compensation cycles at all. To see if TVs were running compensation cycles when powered off, RTINGS measured the TVs' power consumption, looking for a plateauing uptick in consumption for a short duration right after the TVs shut off.

 

 

Differing from what RTINGS' lab saw, when a RTINGS employee tested their own A90J at home, the TV reportedly ran the compensation cycle after 6.5 hours of use.

 

Sony's spokesperson told me that it believes RTINGS lab TVs "were not powered off long enough prior to beginning the compensation cycle," despite RTINGS having claimed otherwise.

 

Sony's rep added that Sony 's OLED TVs "all have the same algorithm for running the compensation cycle. Compensation is designed to start 4 hours after Remote Control Power Off." However, that's not what RTINGS' staff experienced, nor what the support pages I linked to above suggest. At the bare minimum, Sony should update its support pages around this topic or find a clearer, consistent way to communicate this information to users.

 

According to RTINGS, Sony's A8H, which came out in 2020, ran its short compensation cycle after the TV was used for four cumulative hours and then also off for four hours. Sony reportedly told RTINGS that this is because the refresh makes a disruptive click sound. However, this qualification could be problematic for users who, for whatever reason, don't leave their TVs off for four straight hours. However, the A8H lets users manually run short compensation cycles.

 

RTINGS also tested Sony's S90K and A95K and said they consistently ran short compensation cycles after 5 hours and 45 minutes of cumulative usage.

 

RTINGS also ran into trouble when testing its Samsung S95C. Despite its other Samsung OLED TVs and even a Samsung OLED monitor (the Odyssey OLED G8) reliably running short compensation cycles after four usage hours, the S95C, which Samsung released this year, wasn't as consistent.

 

RTINGS' rep said:

The newly added S95C doesn't seem to run [short compensation cycles] consistently or really at all. Just how and when they're triggered is a mystery. We even toyed around with different settings, but none of them could force a compensation cycle, except for the one time we ran it with an internal streaming app and used a remote to turn it off instead of our fancy HDMI CEC Divine Master of 100 TVs Setup. But we couldn't repeat that. We also managed to trigger the short compensation cycle by unplugging the TV and plugging it back.

RTINGS suggested that unplugging the TV "might be a fix" for the S95C lacking a way to manual-launch a short compensation cycle. Samsung's S95B also doesn't let users run short compensation cycles on demand, RTINGS noted.

 

Samsung didn't respond to Ars Technica's request for comment for this story.

 

OLED TVs that RTINGS tested from LG, as well as the one LG monitor it looked at (LG's UltraGear 27GR95QE-B), ran short compensation cycles consistently after four hours of use, RTINGS reported.

 

That's especially critical since several LG TV models RTINGS examined don't let users launch short compensation cycles:

 

• LG B1
• LG B2
• LG C1
• LG CX

 

Allowing users to run short refreshes at will would ensure users have a quick, reliable way to immediately get rid of image sticking they might encounter.

 

Many TVs offer a long compensation cycle that users can implement manually, but Sony's spokesperson confirmed to me that such compensation cycles only address burn-in related to the electroluminescent layer, not TFT-related temporary image retention.

Is HDMI CEC to blame?

RTINGS couldn't immediately confirm why some of its TVs didn't run short compensation cycles as expected but suggested that, at least in the case of the Sony TVs, it could have to do with HDMI Consumer Electronics Control (CEC), which lets you control up to 15 devices connected via HDMI with one remote.

 

"Our best guess for this discrepancy is some buggy implementation that doesn't play too nicely with HDMI CEC. The compensation cycles seem to work fine when you turn the TV off with a remote control albeit, much later than 4 hours," RTINGS' spokesperson said regarding Sony's A80J. 

 

However, Sony's rep said this isn't the case.

 

"A power-off command with CEC has the same effect as a power-off command from a Remote Control. The compensation timer will begin from the Remote/CEC off command timing," they said.

 

A Samsung UK support page at least seems to suggest that you should turn off the TV "using the remote or the power button" on the device to run the TV's short compensation cycle.

More to learn

RTINGS is still working to understand how different types of compensation cycles address different types of image retention on OLED screens. Its video Friday also admitted to previously mistakenly reporting temporary image retention on some Sony WOLED and Samsung QD-OLED TVs as potential burn-in.

 

"We were wrong in that assertion," RTINGS' spokesperson said. "We didn't know enough about the nature and characteristics of image retention on OLEDs to be able to make that claim."

 

Yet, RTINGS is a respected, detailed review publication that has done much research in this space. Its confusion highlights the complexity of OLED image persistence. Anything that can be done to alleviate concerns about this issue, especially as OLED TVs become more common, would be welcome. It also suggests that TV vendors should do a better job of detailing this sort of information themselves. Many, like Samsung and LG, typically avoid a serious deep dive into OLED image retention.

 

RTINGS, on the other hand, really gets into it when it comes to panel longevity. You can keep up with its ongoing TV longevity test here and watch its eight-month update video below:

 

My favorite video.