A few days ago Apple was awarded with 52 different patents, covering a wide range of technologies that include 3D glasses, in-air gesturing, fingerprint sensing and more.

One of these patents details a Micro-LED device that is able to both emit and sense light. We have seen similar solutions based on OLEDs - in that case the photo-diodes were placed between the OLED pixels, to create a micro-display that can sense light (possible applications are for example eye-tracking in a VR headset).