Samsung is expected to launch three variants of the Galaxy S10 next year and apparently, all three variants will sport in-display fingerprint sensors with the two higher-end variants housing an ultrasonic scanner and the third lower-end model featuring an optical scanner. The use of in-display fingerprint sensors is expected to define the overall smartphone market next year.
https://www.notebookcheck.net/In-display-fingerprint-sensor-to-grace-all-Samsung-Galaxy-S10-variants.327228.0.html