The first smartphones had full, physical keyboards featuring not only the entire alphabet, but all the punctuation and other keys necessary to communicate. Since then, though, makers have been working to remove every single button and port from each new generation of devices. Qualcomm is taking one more step in that direction with its new under-screen fingerprint sensor, shown off in its prototype phase in a modified Vivo XPlay 6 phone at Mobile World Congress 2017.
This new tech uses an ultrasonic signal to transmit the fingerprint data, and it will come to phones in two phases. First, we'll get fingerprint sensors that integrate into glass and metal bodies. These sensors can sense prints through 800µm of glass and 650µm of aluminum, compared to the previous 400µm limit. The display sensor will come a bit later, and will allow for fingerprint detection through OLED displays up to 1200µm thick. The new sensors can even read a print under water and detect heart beat and blood flow, Qualcomm says. That functionality should make it harder for someone to gain unauthorized access to a device using a fake fingerprint.
The sensors are designed to be integrated with Qualcomm's Snapdragon processors, though they'll also be available as standalone units for use with non-Snapdragon platforms. The glass and metal sensors are designed to be compatible with the Snapdragon 660 and 630, while the sensors that work with glass, metal and displays will be compatible with "future Snapdragon Mobile Platforms and non-Snapdragon platforms." Qualcomm VP of Product Management Seshu Madhavapeddy told CNet that current and future generations of products will work with this technology. "There's really nothing that needs to be upgraded to support this," Madhavapeddy said.
Engadget says the tech as implemented in the XPlay 6 is a bit laggy, but works as intended. The site also says that the detection window in the test XPlay is a small, marked portion of the screen. The demonstrators told Engadget that applying the sensor to the entire screen would increase the price significantly, but it sounds like manufacturers could cover, for example, the entire bottom third of the screen and leave the other two thirds free—thus offering a compromise between usability and price.
Rumors are floating arround suggesting that the next iPhone will ditch the dedicated fingerprint sensor as well. As CNet notes, though, relations between Qualcomm and Apple aren't so hot right now thanks to a royalty suit. In turn, it's entirely possible that Apple could be using its own tech for that functionality.
The glass and metal sensors will be available to vendors soon, and Qualcomm expects to see them in consumer phones in the first half of 2018. The display sensor won't be available to vendors until the fourth quarter of 2017, so we should expect handsets packing those a little bit later.