Xiaomi has been slower to adopt in-display fingerprint sensors than some of its Chinese rivals, only including the feature on certain high-end variants of last year's Mi 8 flagship phone. But according to a Weibo post by president and co-founder Lin Bin, the company is working on a much more advanced implementation of the technology.

Lin's post includes a video demonstrating a prototype phone with a new fingerprint sensor that has an active area of 25 x 50mm, meaning users could unlock it by tapping anywhere within a much larger region than the thumbprint-sized scanners found on several phones released last year. It would represent a boon for usability, particularly since you wouldn’t have to look for the physical location of the scanner while picking up the phone. Lin also says the new sensor is able to wake and unlock the phone with a single tap.

Xiaomi isn't the only company working on larger in-display fingerprint sensors. Early last year Vivo showed off a concept phone called the Apex which featured a "half-screen" sensor; it was more like a third in reality, however, and was missing from the Nex, the eventual shipping version of the Apex. And just this week Oppo announced that it'll release phones this year with a fingerprint sensor that's 15 times larger than previous implementations, although it didn’t provide specific dimensions. Lin hasn’t said when Xiaomi might put its own version into a shipping product.

Chinese companies, particularly Vivo, drove the adoption of in-display fingerprint sensors last year, and it’s only in 2019 that international competitors like Samsung are said to be catching up. The question now is who will be first to commercialize the next generation of the technology, and will it work well enough to be a selling point?