Nearly a year ago we wrote about a Microsoft patent for USB-powered Surface Pen loop which would also charge the active pen. Since then, however, Microsoft has released a number of Surface products, including the Surface Pro 4 and Surface Studio, where the pen is magnetically attached to the device, making the Surface Pen loop, charging or not, rather redundant.
In response, the inventors of the USB charging loop, Shiu Ng, Senior Hardware Engineer at Microsoft Surface, at Tim Jakoboski, Director of Hardware Engineering at Microsoft, have updated their patent to now include inductively charging elements in the casing of the PC, where the pen is held accurately and securely in place using strong magnets.
Microsoft notes that due to the induction coil being small and now flat, they would be able to integrate them not just in the edge of the tablet, but also in other locations such as the back of the device, or more interestingly, behind the surface of the screen, allowing Microsoft to for example charge the Surface Dial directly from a hotspot on the screen itself.
Another option would be to integrate the inductive charging coil in other peripherals, such as on the detachable Surface keyboard. There Microsoft suggests that instead of using magnets to accurately place the pen (necessary for efficient charging), to instead use a slot-like depression on the surface of the keyboard in which the pen would only fit in a specific orientation, to achieve the same end.
Microsoft is also proposing to communicate with the active pen directly using modulation of the inductive charge, using a technology such as the Alliance for Wireless Power (A4WP)’s wireless charging protocol, which would allow for 50 kbps two-way data transfer, allowing for communication about items such as charging state or for firmware updates to the pen.
The patent was filed on the 12th May 2017 and while there is no guarantee that this patent will result in a device, it appears very detailed, suggesting it is more likely than not.