Internal documents outlining Microsoft's future hardware plans have leaked, giving a sneak peek at what the next couple of years of the company's hardware are likely to look like, writes Brad Sams of Thurrott.com.

First up, there's a trio of Surface-branded devices with the code names Carmel, Libra, and Andromeda. Libra is the cheap Surface tablet that Bloomberg reported in May. This isn't Microsoft's first foray into the cheap(er) tablet market; while the focus of the last few years has been on the more expensive Surface Pro, it seems that Redmond continues to regard it as an important segment, with the education market a particular target. Should Libra make it to market, it's expected to become available this year.

Carmel is the next iteration of the Surface Pro. Intel is going to refresh its mobile processors later this year, with processors codenamed Whiskey Lake and Amber Lake—the former with a power consumption of about 15W, the latter of about 4.5W. These will continue to use the "8th generation" branding, and either or both could make sense in some kind of Surface product. This processor timeline means it's unlikely we'll see Carmel before Whiskey and Amber Lakes hit the market; however, the documents apparently don't provide any hard dates for when it's due.

They do, however, say that Andromeda, Microsoft's mythical pocketable, two-screen, hand-held device that's supposed to carve out a whole new market for itself, is due for release in 2018. The documents also say that, after Andromeda, Microsoft OEMs will produce their own comparable products, just as they've done with Surface Pro.

The big question for Andromeda is the same as it has always been: why? To define a new hardware form factor, as appears to be the intent, its design needs to be particularly suitable for something. Surface Pro, for example, has appealed particularly to groups such as students (taking notes with OneNote) and artists, thanks to its form factor and multimodal input support. To succeed, Andromeda needs to offer similar appeal—it needs to enable something that's widely useful and ill-suited to existing hardware. But presently, there are few ideas of just what that role might be.

Next up, in 2019, is a new version of HoloLens, codenamed Sydney. The documents say it is due to hit the market in some capacity (for developers or perhaps full commercial availability) in the first quarter of 2019. It will be much cheaper than the current HoloLens (though how much cheaper isn't known at this time), as well as lighter, more comfortable, and with a much better display. It will probably use a new sensor package derived from the Project Kinect for Azure announced at the Build developer conference last month and will also probably incorporate Microsoft's second-generation holographic processing unit custom processor.

Finally, the next-generation Xbox that was confirmed to be in development earlier this week is due for release in 2020 and has the codename Scarlett. The documents also suggest that Scarlett may not be a single piece of hardware but instead a family of devices. Given Microsoft's prioritization of backward compatibility and the ability to move your game library from generation to generation without having to re-buy or keep old hardware hanging around, it's reasonable to expect that Scarlett will be, broadly speaking, a faster iteration of the current Xbox One X.

One note of caution is that the documents were produced during Terry Myerson's tenure as head of the Windows and Devices Group. With Myerson leaving the company, it's possible that Microsoft's plans have changed.