Samsung Display's new QD-OLED displays use a special triangular pixel structure that can cause color fringe artifacts. The company does not see it as an issue in the "vast majority of use cases".

QD-OLED's pixel structure
The triangular pixel structure of QD-OLED was first highlighted by German magazine Heise.de (1, 2) in their test of the first QD-OLED monitor. Heise demonstrated how it can result in color fringe artifacts near edges of especially text or clearly defined objects in the picture, but also sometimes in games.

- "In the latter case (Cyberpunk 2077), the display had something of a built-in shallow chromatic aberration – but the effect in the moving game is not as noticeable and annoying as in the static desktop," said Heise.

Here is an example:


 Example of color fringe artifacts caused by QD-OLED's triangular pixel structure. Photo: Mark Mantel, Heise

Why has Samsung Display, the manufacturer of the QD-OLED panels, chosen to position the three red, green and blue subpixels that together form each pixel in a triangle rather than using the more conventional RGB stripe layout?

QD-OLED pixel structure. Photo: Ulrike Kuhlmann, c't
- "It is not a typical RGB stripe pixel – but our proprietary structure optimized to enhance the core user experience of color and HDR. We selected this new pixel structure in order to optimize optical characteristics of QD-Display like brightness, color gamut and durability. Each pixel of QD-Display has an individual Red, Green and Blue – 3 primary sub pixels," Samsung Display said in a statement to FlatpanelsHD. 

- "Unlike Pentile sub-pixel structure that share the adjacent sub-pixel and compromise on detail and accuracy, QD-Display has 3 (R,G,B) x (3440*1440) sub-pixels. So, QD display does not compromise on the detail and accuracy."


Samsung: Can also happen with RGB stripe
Samsung Display further argued that similar color fringe artifacts can be seen on conventional RGB stripe-based displays but that displays with high contrast modulation and a wider color gamut, such as QD-OLED, can accentuate the effect.

- "The artifact pointed out also can be seen on conventional LCD and OLED displays using RGB stripe. Similar phenomenon is observed on the sides (Left and Right) side 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."

 Also read: QD-OLED is cheaper than expected

Although the color fringe effect can reportedly be seen on QD-OLED displays when sitting close to the screen, Samsung Display believes that it will not be an issue in the majority of use cases. The company has positioned its first QD-OLED monitor panel as a gaming solution while the first QD-OLED TV panels are intended for both video and gaming.

- "Having said that we believe that for the vast majority of use cases this is not an issue. For life-like color and HDR performance (Cinema and gaming) this display will provide the most elevated experience," Samsung Display told FlatpanelsHD.

Dell has already launched its first QD-OLED monitor while Sony and Samsung Electronics will soon launch the first QD-OLED TVs (Sony A95K and Samsung S95B). Samsung Electronics will also launch a QD-OLED monitor later this year (Samsung G8QNB).

FlatpanelsHD will later receive QD-OLED review samples and will provide an evaluation of the pixel structure and how it affects the viewing experience.

- Source: Heise, Samsung Display