In the video a prototype cellphone that uses a new fingerprint sensor that has an active area of 25x50 mm is seen. That is, users can more easily unlock their cellphones with a larger area without looking at the screen.
Usually, cellphone manufacturers only provide a small area - usually only the size of the thumb - where the fingerprint sensor is stored. As a result instead of making it easier to use, the user must even make sure that his thumb touches the right screen to unlock the cellphone.
Quoted from the page of The Verge, Friday (1/18), Lin also called this new sensor can 'wake up' and unlock the phone with just one touch. But keep in mind, Xiaomi is not the only company that works on similar technology. Vivo had previously exhibited Apex, which half of the screen could be used to recognize fingerprints.
Unfortunately this technology is not implemented on Nex, which is a commercial version of Apex. Then there is also Oppo who claims the fingerprint sensor below the screen has an area 15 times larger than the previous implementation, although it doesn't mention its specific size.
But Lin also did not mention whether this technology will be implemented in commercial products. Because the cellphone in the video on display is just a prototype product.