Xiaomi works on improvment Fingerprint on display scaner.

1) One-click entry: as long as you do a fingerprint entry, you can do screen fingerprint unlock without having to repeatedly enter multiple times.
2) Wide-area blind solution: The screen fingerprint unlocking area is up to 25mm x 50.2mm, which is many times larger than the unlocking area of ​​the mainstream mobile phone on the market. It can be unlocked without looking at the screen.

Source: Youtube