Microsoft's researchers have created a dual-screen variant of the company's Surface tablet computer, with the additional, E Ink screen positioned north of the keyboard in the device's cover.

A YouTube video, first reported on by Neowin and posted by Microsoft's Applied Sciences Group (basically, Microsoft's R&D group for computer interfaces), showcases a prototype of such a device. The E Ink screen is used as a Start Menu, an app launcher or as a secondary display that enhances an app's functionality — for example, it can be used as a thumbnail browser for a photo-viewing app.

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Since the E Ink screen is multi-touch, it can also be used as a sort of an expanded trackpad — for example, you could use it for zooming in and out of a map, or as a writing surface for a stylus.

Probably the most interesting thing about the video is the fact that the prototype seems to be a very mature one — the functionality is there, and even the design doesn't look too far from a finished product. This of course doesn't mean this device will soon (or ever) see the light of day, but it's nice to see Microsoft is constantly innovating to make its Surface tablets better.

Microsoft has had some radical ideas about the Surface before. In Jan. 2015, the company introduced the Surface Hub, an 84-inch 4K touchscreen display, mainly intended as a visualization tool and for presentations.