Apple is secretly developing its own display technology for use in future iPhones and Apple Watches, according to a recent Bloomberg report.

It’s claimed that around 300 Apple engineers are working on so-called MicroLED screen technology at a secret California manufacturing facility, where a small number of screens is being produced for testing purposes.

MicroLED works on similar principles to the OLED screen technology found in the iPhone X and Apple Watch, whereby pixels are individually lit. In both cases this leads to much greater contrast levels than LCD.

However, MicroLED goes even further than OLED. By using different light-emitting compounds, it can increase brightness and power efficiency over that of the existing technology.

It’s an incredibly difficult technology to master, to the point where Apple was reportedly close to killing MicroLED operations altogether around a year ago. Progress now appears to have been made, and Apple could introduce MicroLED into the Apple Watch range some time over the next couple of years. It’s unlikely to reach the iPhone family for another three to five years.

Apple’s interest in MicroLED technology can be dated back to 2014, when it purchased a company called LuxVue. Prior to its purchase, this secretive display specialist had filed several patents for next-generation MicroLED screen technology.

Up to now, Apple has used displays made by other companies in its products. The iPhone X, for example, uses a custom OLED display from arch rival Samsung, while the current Apple Watch screen is made by LG Display.

With Samsung dominating global OLED display production – and reportedly charging a hefty price for each iPhone X screen – it’s no surprise to learn that Apple is looking to take control of this key component for future devices.