The new OLED tech uses films to emit white light between reflective layers, one silver and another made of reflective metal with nano-sized corrugations.

This "optical metasurface" changes the reflective properties and allows specific colors to resonate through pixels. The design allows for much higher pixel densities than you see in the RGB OLEDs on phones, but doesn't hurt brightness to the degree you see with white OLEDs in some TVs.

This would be ideal for VR and AR, creating a virtually 'flawless' image where you can't see the screen door effect or even individual pixels. This might take years to arrive when it would require much more computing power, but OLED tech would no longer be an obstacle.