In-display fingerprint sensors have been around for a couple of years now but it is often found on smartphones with an OLED display. This is because OLED is capable of lighting up selected pixels for illumination and the fingerprint can be picked up by the optical scanner. Unfortunately, this doesn’t work on cheaper LCDs as it uses backlight for illumination. However, it now appears that Xiaomi’s sub-brand Redmi may have just found a solution for LCD panels.
According to Redmi General Manager, Lu Weibing, its R&D team has managed to overcome the problem of implementing in-display fingerprint sensor for LCD devices. Their solution uses an “infrared high-transmittance film” and an infrared transmitter at the bottom of the screen that emits infrared light. This will allow the fingerprint to be reflected through the screen and onto the fingerprint sensor for verification.
He has also shared a demonstration video of a prototype Redmi Note 8 Pro and it appears to unlock just as quick as an OLED based in-display fingerprint sensor.
If this solution is massed produced, devices with LCD displays can offer a cleaner exterior design without a rear-mounted fingerprint sensor. At the moment, the best alternative is to implement a side-mounted fingerprint sensor like the Redmi K30 and Honor 20 series.
Would you prefer a device with an in-display sensor or a physical fingerprint sensor? Let us know in the comments below.
