VESA Rolls Out Updated DisplayHDR Standard for OLED Displays: DisplayHDR True Black
Blaze Display Technology Co., Ltd. | Updated: Nov 27, 2018
Recently the VESA is rolling out an update to the standard body’s DisplayHDR monitor performance standard that’s focused on expanding the specification to cover OLED displays. Dubbed DisplayHDR True Black, the new performance tiers to the DisplayHDR standard are intended for OLED and other emissive displays, laying out the levels of display performance that the association believes are appropriate for consumer HDR displays.
This update comes just over a year after the original DisplayHDR standard was launched. Intended to simplify the market for HDR displays, DisplayHDR sets a number of tiers of increasing performance, with each higher tier requiring better monitor technology and delivering a better HDR experience as a result. At the time of DisplayHDR’s launch, the VESA opted to focus on LCDs, as these displays were already in the PC market and were what the association had the most experience with. The end result was the DisplayHDR 400, 600, and 1000 standards, which covered a range of monitor designs that essentially stretched from not-very-HDR to cutting-edge full array local dimming displays.
The DisplayHDR True Black update in turn adds two more tiers to the DisplayHDR standard: DisplayHDR 400 True Black, and DisplayHDR 500 True Black. Like the tiers for LCDs, the True Black tiers are divided up based on performance; though the gap isn’t quite as big as with the LCD tiers. The end result is that displays reaching these standards, besides meeting the DisplayHDR specification’s baseline requirements, can also hit a peak brightness of 400 nits and 500 nits respectively.
The need for separate tiers for OLEDs – and other future emissive technologies like microLEDs – is rooted in the fact that HDR itself is as much (or more) about dynamic range as it is absolute maximum and minimum brightness. While LCDs can offer the necessary contrast ratios with the right backlighting technology, they are still backlit displays, meaning that they can’t quite hit black since they’re always illuminated to a degree. OLEDs, on the other hands, can hit almost perfect black levels since the pixels can simply be turned off entirely – hence the True Black moniker – which means these displays need to be measured on a different scale. Conversely, while LCDs can sustain incredible 600+ nit brightness levels over the whole screen, OLED technology can only burst to these levels for short periods of time, so the maximum brightness offered by OLED displays isn’t quite in sync either with HDR LCDs.