Concerns have been raised over Samsung Display’s new QD-OLED displays due to their use of a special triangular pixel structure that can cause color fringe artifacts in some situations.
The issue, which was recently highlighted by the German-language website Heise.de, could potentially cause some issues with Samsung Electronics’ new S95B OLED TV and Sony’s new flagship A95K QD-OLED model.
According to Heise, tests done on the new Alienware 34 Curved QD-OLED Gaming Monitor revealed that the pixel structure led to some colour inaccuracies that occur in the pixels between dark lowlights and bright highlights. As such, viewers may see what looks like green or purple pixels between all-white and all-black parts of the screen (see graphic, above).
Heise says the reason for the issue is Samsung Display’s unique pentile pixel design, where the red, green and blue subpixels are arranged in a triangle formation. That’s opposed to being side-by-side in a striped, window-like configuration, as is the case in most other displays.
According to Heise, the issue isn’t especially noticeable in fast-motion scenes, though some users may be perturbed in static images, such as a desktop screen or a logo.
Samsung Display has moved quickly to reassure anyone who might have pre-ordered a new QD-OLED TV or monitor, telling FlatPanelsHD that it’s not uncommon for displays to show some fringe colour artifacts. It added that the same phenomenon is often seen on conventional LCD and older OLED displays that use the RGB stripe sub-pixel architecture.
The company also elaborated on its reasons for choosing the new sub-pixel structure, saying it has been optimised to enhance user’s experience of colour and HDR.
“The artifact pointed out also can be seen on conventional LCD and OLED displays using RGB stripe. Similar phenomenon is observed on the sides when displaying bright high contrast edge on conventional display products," Samsung Display told FlatpanelsHD. "Displays with better contrast modulation performance and wider color gamut and greater contrast ratio will accentuate this artifact. Because QD-Display has the widest color gamut, superior contrast ratio and new sub pixel structure, this artifact could be visible."
Samsung Display’s statement appears to be an admission of guilt, but the company promptly reiterated that the issue is nothing to worry about. While some users may see artifacts sitting up close to the screen, it said it will not be noticeable in the majority of use cases.
“Having said that we believe that for the vast majority of use cases this is not an issue,” the company’s statement continued. “For life-like color and HDR performance (Cinema and gaming) this display will provide the most elevated experience.”
Most likely the issue will be a matter of personal preference. There will be those who aren’t bothered about the colour artifacts or don’t even notice them, while others – perhaps gamers who like to sit close to the action – will react with horror. In any case, it’s impossible to know how bad the problem is without actually sitting in front of a QD-OLED display. It’ll definitely be something to keep an eye out for when it comes to HDTVTest’s first QD-OLED display review, which is coming soon.
