Microsoft are one of the most prolific patent holders in the US. The Redmond firm are well and truly raking it in from licenses relating to the Android OS, and are not shy to slap a patent on just about anything, from augmented reality bananas to emotion sensing smart bras.

Many of these inventions may never see the light of day and are simply intended to fend off rivals, but these latest patents when combined with recent comments from Lumia marketing VP Tuula Rytilä create an intriguing possibility.

"This disclosure relates to hinge mechanisms for mobile electronic devices, such as mobile phones and mobile computers." Conventional hinged mobile electronic devices, such as "flip phones", typically include two body portions or leaves, hinged about a single pivot axis. In the closed position, this single pivot axis is positioned even with the plane of contact between the two leaves. Because of this geometry, the two leaves cannot open 180 degrees and/or the hinge protrudes upward out of the plane with the leaf faces.

Essentially what Microsoft seek to solve with this latest patent is the inability for flip phones to open to a horizontal 180 degree angle without some form of trade-off, like having the hinge protrude out of line with the flat plain created by opening the two halves. Lenovo recently achieved this feat with their Yoga 3 Pro and its unique hinge, pictured in the lead photo for this article.

"Disclosed herein are embodiments of multi-axis hinge mechanisms for mobile electronic devices that allow for at least 180' determinate pivoting motion between two portions of the devices."

Although flip phones feature hardware keyboards in the second portion, the drawings above seem to represent screens pressed against each other. Companies in the Android contingent have toyed with dual-screen phones, but none have thrown their full weight behind this form factor as of yet.

I got to speak with the Lumia marketing VP at Mobile World Congress 2015 a few weeks back as part of a group of fans and tech bloggers. When responding to criticism that Microsoft weren't creating enough differentiation between the low-end and high-end Lumia phones, Tuula praised the innovation of the Surface Pro 3, citing that the Lumia team would look to bring that spirit of invention to future devices.

"When we think about high-end phones, I don't think that a 5-inch rectangle is the end of how we want to work or live when we're mobile and using mobile technology. I think there's a lot of ways we can still innovate and reinvent and for us as a challenger in that space that's what we need to do."

Could these patent drawings represent future Lumia phones? The option for a second screen to display a second app or a larger qwerty keyboard is quite an enticing one. Considering Microsoft's focus on productivity, it seems likely that the chaps at Redmond are at least toying with these sorts of dual screen designs.

Source: US Patents Office