Burn in and Image Retention

Review web site Rtings.com has performed an extensive accelerated longevity test for over three months, testing the latest QD-OLED and WOLED TVs.y 

Rtings reports that both QD-OLED displays (Samsung S95B OLED and the Sony A95K) showed signs of image retention, and it seems in general that the QD-OLED displays suffer from worse problems compared to LG's WOLED. Some of Sony's WOLED TVs also showed signs of image retention.

Japan Display (JDI) announced that it has developed a new OLED deposition technology, which they refer to as eLEAP, that is cost effective and can be used to create OLEDs that are brighter, more efficient, and longer lasting compared to OLEDs produced using mask evaporation (FMM). eLEAP also enables OLED freeform deposition. JDI regards its new technology as a " historic breakthrough in display technology".

eLEAP is based on a lithographic method, and does not require any masks. The main advantage seems to be that OLED displays produced by eLEAP technology can achieve an aperture ratio of 60%, compared with FMM OLEDs which achieve a ratio of about 28%. This means that the OLED displays can be driven at lower currents - which extends the lifetime, improves the efficiency and also enables higher-peak brightness when needed.

A YouTube technology reviewer Bon Wulff has performed a five-months long test of its Nintendo Switch OLED console, trying to estimate the burn-in problem in the device's AMOLED display. He used a static image, running it for hours, checking for any visible burn-in issues.

It turns out that it took 3,600 hours of nonstop projection of the single image for the AMOLED to exhibit any visible burn-in problems. This is an extreme test, which is a great testament to the durability of modern AMOLED displays, and a great reassurance to all the consumers who are worried about OLED display burn-in.

Back in 2020 we reported that Apple is worried about lifetime and burn-in issues in AMOLED displays in tablet applications, and Apple decided to adopt a tandem OLED architecture in the displays it will eventually adopt in future iPad devices.

LG Display already developed such panels for automotive applications, and according to reports it is developing a tandem LTPO AMOLED display for Apple, aiming to supply these to Apple at around 2024. According to a new report, Samsung Display has launched a project to develop tandem OLED panels as it also hopes to supply panels for Apple's future iPads.

A few days ago we posted that Apple has reportedly decided to delay its iPad OLED launch to 2023, and the company canceled its current joint development project with Samsung Display, as SDC could not develop what Apple wanted - a tandem stack structure, which would have improved the lifetime and performance of the AMOLED display.

According to a new report from Korea, LG Display is also developing a tablet display for Apple - a 12.9" AMOLED panel. LG's iPad display will be ready for mass production by 2023-2024, and it will use a tandem (2 stacks) architecture on an LTPO backplane. As SDC's project is canceled, it is likely that LG's 12.9" will be the first OLED adopted by Apple's tablets.

In the last couple of years, we have seen OLED displays starting to be adopted in high-end laptop devices, and recently prices of OLED laptop panels have dropped and more mid-range laptops have opted for OLED displays (usually as an optional upgrade over an IPS LCD).

I recently bought a new laptop, the Lenovo Yoga Slim 7i Pro OLED, with a 14-inch 2880x1800 (2.8K) 90Hz AMOLED display. The screen, as expected from an OLED, looks brilliant. Some people are still concerned about OLED in laptops, though. Some worry that the display might suffer from burn-in.

MicroLED displays are exciting to many, as the technology seems to be the front runner for the next-generation display of choice in many market segments - from AR/VR glasses through wearables to TVs and IT displays.

The MicroLED industry though, even after billions of dollars spent on R&D, is still at a very early stage. Production costs are high, processes are not reliable enough, and there are several technical challenges to overcome before production can begin (except for some niche areas such as ultra large-size premium TVs).

OLED compensation technology developer IGNIS Innovation launched an interesting new system that can be used to inspect and fix burn-in problems in Android smartphones.

The system, which IGNIS calls an Automated Optical Inspection System (AOIS) is a tabletop machine that you insert an Android smartphone into, and it identifies areas with image retention. Using software drivers, one can then compensate for these problems. The compensation is based on IGNIS proprietary MaxLife compensation technology.

In a very interesting post, The Elec states that Apple has reached out to both Samsung Display and LG Display, requesting that the display suppliers develop a longer-lifetime OLED display for Apple's next iPad Pro devices.

LG 12.8-inch P-OLED in Mercedes Benz 2021 S-Class

The lifetime of the current crop of mobile OLED devices is not enough for Apple's iPad - which is designed to be used for a longer period of time compared to a smartphone. An increased lifetime will also result in lower burn-in problems which seem to trouble Apple.

In October 2019 Samsung Display formally announced its decision to invest $10.85 billion in QD-OLED TV R&D and production lines. The company is already starting to produce prototypes, and is on track to start mass production in Q3 2021.

But SDC is facing a problem it probably did not anticipate - Samsung Electronics is hesitant about the adoption of QD-OLED panels, and may not ship QD-OLEDs in 2021 - or maybe even at all. Apparently Samsung Electronics wants to focus on microLEDs for next-generation displays as it finds QD-OLED TVs to be not bright enough - and also because it suffers from burn-in issues.