Apple's new "dual display" patent could potentially allow for a future MacBook or iPad to use a second screen in place of a keyboard, eschewing physical keys.
The United States Patent and Trademark Office has granted Apple a patent titled "dual display equipment with enhanced visibility and suppressed reflections." The documentation for what is patent number 9,904,502 outlines a device that would use a second display as a dynamic keyboard.
Two implementations of this design are described in the patent application, according to Patently Apple. The first utilizes a permanent hinge, while the second allows the screen to be removed and used separately, along the lines of Microsoft's Surface Pro range and other two-in-one computers.
The patent documentation makes it clear that the implementation is not intended as an accessory that would allow two iPads to be paired together, with one serving as the keyboard. Additionally, illustrations associated with the application explicitly state that one screen is an OLED display, while the other is an LCD.
A double-display set-up could provide easy access to a different keyboard layout language, context-sensitive controls, or even a large sketching surface to use in conjunction with something like an Apple Pencil. However, that flexibility would come at the cost of the traditional typing experience offered by a mechanical keyboard.
Apple's patent addresses the fact that using a second display as a keyboard could result in unwanted reflections between one screen and the other. Polarizer layers and wave plates would be used in both displays to prevent any such glare.
Apple has already flirted with the idea of a dynamic keyboard in part, in the form of the OLED Touch Bar that was introduced to the MacBook Pro line in 2016. Presenting the entire keyboard in this manner would seem to be one possible evolution of that idea.
Many of Apple's patented inventions don't make it to market. At present, there are no rumors suggesting that Apple is actively working on this concept with any of its partners or is close to bringing it to market.