A patent recently granted to Apple imagines replacing a typical laptop keyboard with an OLED display for “dual display equipment with enhanced visibility and suppressed reflections” with two screens connected by a hinge. But the patent describes two final versions of the product, one resembling more of a MacBook with both screens permanently attached as a single device while the other utilizes the second screen display as a magnetically detachable accessory.
With two screens being used, there’s also a concern for whether or not they might reflect onto each other so Apple addresses this by describing use of polarizer layers and wave plates to minimize unwanted reflections.
Historically, Apple has expressed interest in OLED integration with their devices as they have also filed patents with a similar concept even as far as ten years ago. But these had only come into fruition two years ago with the launch of OLED Touch Bar as a feature on the 2016 MacBook Pro.