
As OnePlus spins up the hype train leading up to the unveiling of a ‘concept' smartphone at CES 2020 they are announcing many future-facing features including having all cameras hidden.
OnePlus as a company is extremely fond of cultivating hype in the lead-up to new product launches, and the brand's first ‘concept' phone – a smartphone with many future-facing features that are currently infeasible for consumer hardware – is not lacking it.
OnePlus keeps leaking new details of their ‘Concept One' smartphone almost daily, and the last few days have revealed some intriguing features alongside the sketch/outline of the McClaren-designed device above which appears to feature what may be a leather rear panel surrounding a glass strip.
Those features yet announced are the fact that all the cameras – both on the rear and front – will be hidden when not in use on the Concept One, using different technologies for each side to meet their needs.
This feature for the selfie camera(s) is powered by the semi-transparent display technology we've been seeing some companies like Oppo show off, where a small section of the OLED panel at the top of the display can be made semi-transparent to allow a (somewhat hampered) camera sensor to see through.

On the rear though, all three cameras (which are purportedly identical to those of the OnePlus 7T Pro) will be housed in the aforementioned glass strip; but unlike every other phone on the market, that glass strip will not be just tempered glass, but a type of ‘electrochromic' glass which is opaque when current is not supplied to it.
This electrochromic technology allows the rear camera housing to appear as just a smooth glass panel when not in use, but fade to transparent when the rear cameras are needed. There's no guarantee that this won't impact image quality however, and OnePlus has stated that the technology has made the Concept One thicker and more power-hungry while also introducing new reliability issues for the phone. Hence ‘concept phone'.
We'll undoubtedly learn more about the phone over the next few days leading up to its official unveiling at CES 2020, stay tuned!
Source: XDA Developers