Amid speculation about Samsung's future plans for TV technology, the company today delivered another very clear signal that they are focused on Quantum Dot for TV. According to Hyun-seok Kim, President of Samsung Visual Display, who spoke recently with The Korea Herald
I have always said it would take two to three years to consider OLED TV. But now when little progress has been made on its tricky production and high costs since our suspension back in 2013, I wouldn’t say OLED is our future direction... Starting this year, the quantum dot TVs are being launched globally. We will become the No. 1 TV maker for the 11th consecutive year.
During the interview Hyun-seok hinted that the future roadmap for Quantum Dot displays played a role in Samsung's thinking, saying, "It is also likely that new technology like quantum dot could progress faster than OLED."
Beyond fundamental issues around manufacturing at scale, longterm reliability and cost that OLED faces, there are three key image quality performance advantages for Quantum Dots that he's likely referring to here– color, peak luminance and contrast. Quantum Dot technology has been rapidly innovating in these areas over the last few years. Here's a very brief look at how Quantum Dot stacks up to WOLED TV today and where I see the technologies heading next.
What about color? Some Quantum Dot displays have already shipped with color gamuts that go beyond 90% of the ambitious BT.2020 color gamut used by UltraHD Blu-ray discs while WOLED displays have a fixed color spectrum that limits the technology to around 70% of BT.2020 colors. There’s no clear path forward for better color in WOLEDs without significant changes to underlying manufacturing and materials.
In terms of luminance, today's Quantum Dot TVs (1,200 nits) already deliver more than double the nits of White OLED TVs (540 nits).
If 1,200 nits seems excessive, it’s not. Our eyes are capable of taking in much more and we commonly encounter hundreds of thousands of nits in typical outdoor settings in the real world. For TV viewing, typical consumers have also shown a significant preference for higher peak luminance. One recent test conducted by Multimedia Signal Processing Group found that “the preference of an average viewer increases logarithmically with the increase in the maximum luminance level at which HDR content is displayed, with 4,000 [nits] being the most attractive option.” In layman's terms– brighter is better.
While the roadmap to higher luminance Quantum Dot displays is clear (Quantum Dots are already being deployed in professional displays with 2,000 nits of peak luminance), there are big obstacles for WOLED to overcome due to its current-limited design. Even with the help of a sub-optimal white sub pixel design that limits both resolution and the color saturation of bright colors, there are no signs that WOLED technology can catch up in the near term.
Lastly, there’s contrast. Contrast Ratio is, at it’s simplest, a measure of the luminance of the brightest color a display can produce to the darkest. For a great contrast ratio you want to have very bright brights (peak luminance) and the darkest darks (black level).
WOLED TVs are well known for having excellent black levels. However, studies have shown that consumers are already satisfied with the black levels found in today’s top LED and Quantum Dot TVs. These sets employ Full Array Local Dimming (FALD) technology that modulates backlight luminance to produce black levels that are effectively indistinguishable from OLEDs in typical home viewing environments.
While both approaches offer great experiences for consumers, Quantum Dot will be the technology to beat as it continues to deliver increasingly vivid image quality.