2019's in-display fingerprint reader may be considerably better than 2018's
The next big thing in new and upcoming phones may be the in-display fingerprint reader. This novel technology moves fingerprint (FP) unlocking back onto the front panel of a phone, rather than the rear-mounted readers of yesteryear. This feature is now confirmed to be found in the upcoming OnePlus 6T, and is already to be found in somewhat experimental Chinese phones such as the Vivo Nex Ultimate. However, it seems that they may already have been bettered by the fingerprint readers rumored to be available next year - just about two months from now.
A new leak found on Weibo suggests that the in-display FP reader to be integrated into the OnePlus 6T is of the optical variety. This means that it will emit light in order to build up a two-dimensional impression of the fingerprint to be recorded and used for unlocking purposes. However, it appears that a major competitor, Samsung, has improved on this technique already.
Rumors circulating around the anticipated 2019 flagship, the Galaxy S10, indicate that it too will have an in-display FP scanner. However, this one will apparently be an ultrasound scanner, which can record prints in 3D. This may increase the accuracy and speed of unlocking in the putative flagship. Therefore, as the S series is typically released early in the year, it seems phones such as the 6T will have a very short time in the sun as the model with the latest and most interesting screen-locking method.