Virtual and Augmented Reality (VR and AR) headsets share, on the surface, 90% of the same component parts. However, two key technologies separate the former product category, which has sold in the millions on the consumer mass market, from the latter, which is yet to crack the mainstream market. Near-eye optics form one part of the puzzle, but display systems offer an equal challenge.
AR headsets offer some of the toughest challenges available to today’s display industry. Requirements vary depending on the intended application and the optical technologies the displays are paired with, but a typical AR headset might require its displays be:
- Extremely bright in order to compete with ambient light and pair with inefficient waveguide optical combiners – yet power-efficient enough to allow a reasonable battery life without making the headset too heavy.
- Compact and lightweight enough to fit into slim frames that do not look too dissimilar to normal spectacles.
- At least high resolution enough for good legibility of text and notification content, or even full Mixed Reality (MR) experiences.
- Low-cost enough not to blow the bill of materials budget for the headset.
As detailed in IDTechEx’s report “Displays for Virtual, Augmented and Mixed Reality 2024-2034“, meeting all of these in the same package is no easy task, and there are multiple potential approaches. This begs the question: which display technologies will dominate the next generation of AR devices?
MicroLED microdisplays on the way to mass adoption?
MicroLED microdisplays might be the most hyped AR display technology and are an increasingly common choice in minimalist AR devices which are aimed more at minimizing intrusion than maximizing immersion for the wearer. So far, China’s Jade Bird Display (JBD) has led the way here, with its microdisplays finding their way into headsets from players including Vuzix, TCL and Oppo: indeed, IDTechEx is not aware of any microLED-powered AR headsets on the market not using JBD’s panels.
MicroLED displays offer special advantages in terms of brightness-to-volume ratio (unlike many competing technologies, these panels emit light directly instead of being illuminated by a separate light source, which adds bulk) and maximizing pixel density, but there are significant issues to solve. So far, JBD has only been able to offer VGA (640×480) resolution (likely to minimize defect rate in its panels), and if a full-color display is needed, then the outputs of three single-color displays are combined with prisms in the current iteration (JBD says a single panel solution is in the works). However, in the applications targeted so far, these displays more than suffice, with headsets using JBD panels offering compelling visual experiences when demoed by IDTechEx’s analyst.
Laser beam scanning displays: ready for re-entry?
Manufacturing at scale remains the most difficult problem to solve for microLED microdisplays, with complex mass transfer processes and high defect rates being significant roadblocks, keeping JBD alone in serving this market commercially for now. Laser beam scanning (LBS) displays, which draw images using modulated laser beams, could soon offer competition here. They can be made almost as compact as microLED microdisplays (Austrian startup TriLite Technologies’ Trixel 3 LBS display has a volume of less than a cubic centimeter), can couple efficiently with waveguide optics due to their highly collimated output light and, unlike microLEDs, are based entirely on established hardware technologies. It even looked like Google was using the display type in its Project Iris AR headsets, although this project may now be paused or canceled.
However, environmental sensitivity and minute alignment tolerance requirements represent downsides with LBS that have delayed adoption, although software tricks help reduce these issues. Pushing resolution higher without using hardware tricks that can introduce visual artifacts is difficult, but if used in minimalist AR devices, this does not present much of a limitation.
More established technologies show their value
OLED-on-Silicon (also known as micro-OLED) and Liquid Crystal-on-Silicon (LCOS) displays are the more established display technologies holding much of the rest of the AR display market, with good reason. OLED-on-Si offers high resolution at a relatively low cost and is the technology of choice for lower-cost, consumer-focused AR headsets like those from XReal, but their relatively low brightness means they are incompatible with the waveguide optics used in most higher-end devices. LCOS, meanwhile, tends to be the technology of choice for the most immersive MR-capable AR devices, although brightness efficiency and relatively high costs for high-resolution panels present issues here.
Future developments and further insight
What should be clear from the assessment above is that a range of display technologies are likely to maintain their place in AR over the next decade. IDTechEx’s recent report, “Displays for Virtual, Augmented and Mixed Reality 2024-2034“, offers detailed analysis of the spatial computing display landscape. When benchmarking display technologies in this report, IDTechEx found that, as a rule, technological performance was negatively correlated with commercial performance: the question for headset engineer is how much value they place on top-end performance vs. raising prices or making their supply chains hard to manage.
In addition to this benchmarking and in-depth overview of the XR display technology space, the report includes granular ten-year market forecasts and assessments of the potential for success of the technologies covered.
