Microdisplay breakthrough promises to accelerate commercial AR

According to the Cambridge University spin-out, it has only been possible until now to produce blue and green microdisplays using GaN-based light-emitting devices. Red emission has relied on devices based on aluminum indium gallium phosphide (AlInGaP), which has difficulties at the small pixel sizes required by AR, meaning there is an efficiency drop as the device size decreases. Furthermore, to produce a full-colour display, the light from different panels has had to be combined.

In Porotech’s breakthrough all three light-emitting elements can be produced using a single toolchain, removing the complexities of mixing devices based on different material structures. The microdisplay has an active area of 0.55 inches diagonally and a resolution of 960x540.

Porotech raises £3m for microdisplay development

"AR technology is set to be a game changer and micro-LEDs are particularly vital for the advancement of AR interfaces," Porotech CEO and co-founder Dr Tongtong Zhu said in a statement. "In traditional liquid crystal displays [LCDs] the image is a result of both modulating and filtering the light from a white back-lighting module. As such, most of the light created by the panel is wasted by the very working principle of the display. In addition to this inefficiency, the various filtering, diffusion and modulation stages of the LCD display impose limits on how lightweight the final display can be.