Redmi, a Xiaomi spin-off phone brand, says it has made in-display fingerprint sensors that work with LCD screens. Previously, only OLED screens supported them.

HIGHLIGHTS LCD panels are not capable of transmitting light by default, which is why it's difficult to make in-display fingerprint sensors work with LCD displays.

Now, Redmi is showing off a new under-display fingerprint sensor that works through an LCD panel. So far, under-display fingerprint sensors have only been possible on OLED displays.

At the Huawei Developers Conference, the company showcased an LCD display smartphone with an on-screen fingerprint sensor. According to the company, this device will soon go into mass production.

The patent language notes the fingerprint sensor can be stacked with, or part of, an LCD display.

Ultrasonic sensors work using ultrasound to build up an image of your fingerprint (yes, really) and work better with messy fingerprints - if your hands are wet or oily with sun cream, for example.

Xiaomi sub-brand Redmi has demonstrated an LCD smartphone with an in-display fingerprint sensor. This could bring the tech to much cheaper phones.