It all started last year. Samsung launched one QD OLED-TV. A combination of Quantum Dots and OLED had to compete with the W OLED technology from LG. Naturally, questions were immediately asked about it burn-in. But the fact that we are now 10 years after the first OLED TVs, and that a number of important techniques that prevent burn-in were also present in the QD-OLED panels, was reassuring. Anyway, “The proof of the pudding is in the eating”, as they say so beautifully in English. And so it remains to be seen how the first models will age.
Now coincidence (perhaps no coincidence at all) would rtings has just started a large-scale test on the lifespan of TVs. Including the LG G2, the Samsung S95C and the Sony A95K. And guess what? After two months, clear differences are already noticeable. Have a look at the comparison (scroll to the “Accelerated Longevity Test”) between the LG G2 and the Samsung S95B. Or to the LG G2 and the Sony A95K. The differences can be seen on almost all images, the Sony seems to score slightly better.
Those results were a great opportunity for LG to give Samsung a taste of its own. LG Display (the branch of LG that manufactures the W-OLED panels) was also present at the recent press presentation of the new OLED line-up. According to LG Display, the reason for the better results of their own W-OLED panels is precisely due to the presence of the white subpixel in the WRGB subpixel structure. After all, it is not only used to show white, but also to help when colors have to be shown. The extra white subpixel thus ensures a better distribution of the load on the OLED material. QD-OLED uses an RGB sub-pixel structure and can therefore spread the same load less.
And there is a second reason according to LG Display. QD-OLED has a smaller aperture ratio than W-OLED. The “aperture ratio” is the ratio between the luminous part of the pixel area and the total pixel area. According to LG Display, this choice was made to prevent incident ambient light from activating the Quantum Dots too much and diluting it black. But the result is that there is less luminous surface, so more current has to flow through the QD-OLED pixels to produce the same amount of light. And that is precisely what causes faster wear.
Samsung is now in the same boat as LG years ago. That’s painful after all these years of arguing about OLED’s various weaknesses. But on the other hand, this is a first generation of QD-OLED panels. In 2023, Samsung Display will already deliver a next generation of panels that use a new, more efficient OLED material and are equipped with real-time optimized power management. According to Samsung Display, these two aspects not only give the panel a higher peak brightness, but also make it more energy efficient and improve its lifespan. It remains to be seen how big that improvement is. But just like LG has done, Samsung will improve its technology step by step.
Finally, you should keep in mind that the rtings test is a relatively extreme case. It is to be expected that the WOLED devices will also suffer from burn-in. But it should be clear, buyers of the first generation QD-OLED models should avoid long-lasting, static images at maximum brightness. An advice that is still important for all OLED TVs.