Despite the movement towards facial recognition, by the likes of Microsoft’s Windows Hello cameras and Apple’s FaceID, fingerprint sensors still offer the most reliable and convenient biometric authentication, offering not only ease of use but also intentionality ie the user has to take a positive action to unlock their device, vs simply appearing in front of it (or having someone wave it in front of your face).
Fingerprint readers do however take up space on devices and add further manufacturing complexity. Now PengFei Lei, an engineer at Microsoft Asia’s Center for Hardware, has applied for a patent to integrate a fingerprint reader directly into the keys of a keyboard.
Lei suggests using ultrasonics to image the fingerprint, as it works through up to 600 nm of covering, and also suggests the backlight of the keyboard could be used to light up relevant key on the keyboard to guide users to the right button to use.
In some ways integrating a fingerprint reader in the keys is somewhat obvious, so the patent is probably most useful in giving us an idea of in what direction Microsoft may be thinking.
The full patent can be seen here.