Just two days ago, at MWC 2018, Vivo showcased the Apex concept smartphone with in-screen fingerprint sensor and retractable selfie camera. And now a YouTube video reveals details about the in-screen fingerprint capability in particular.
Recently, Vivo equipped its new X20 Plus UDwith the never before seen feature, an in-display fingerprint sensor. Famous YouTuber Zack Nelson, has eviscerated the smartphone to reveal the sensor’s secrets.
The teardown proceeded with the usual meticulous care in order to put it back together again. Of course in the process we see a screen being damaged, which eventually is seen to be replaced by a new one. In terms of a teardown, it looked pretty easy.
Now here comes the interesting bit of the whole teardown. The screen’s glass is seen fused to the display and glued tightly to the frame. Which means, prying it off to get to the sensor would have been risky. Fortunately for the sake of science, that screen was already shattered anyway. And after an excessive amount of heating to loosen up the adhesive, it finally gave way.
This is where Nelson found the diagonally positioned in-display fingerprint scanner, underneath the OLED panel, which was actually translucent. That aided the optical fingerprint scanner to see through the OLED and the glass on top. It is also what makes you almost see the sensor when the screen is turned off. The blackness of the screen is actually due to having a layer of black coating underneath the OLED sheet. Otherwise you’d be able to actually see through the screen. Which would be distracting, yet interesting.
As the YouTuber points out at this point, that while the sensor placement is amusing, the design also mean that users should probably be more careful about about causing cracks rather than scratches. Scratches wouldn’t bother the fingerprint sensing capability of the device much, but the cracks in the screen surely could.