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Redmi shows off first under-display fingerprint sensor on an LCD display [Video]

Under-display fingerprint sensors, for better or for worse, have become very popular on Android smartphones. 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. The thinner design of those display panels makes shining light through the pixels possible in the first place, and ultrasonic uses a similar method to read a fingerprint. That’s complicated to replicate on LCD panels, though, since the entire display is constantly lit.

Now, Redmi is showing off the same idea but for LCD displays. This new technology, detailed in a post on Weibo (via Android Authority), uses infrared light to read a user’s fingerprint. An executive explains:

The innovative use of infrared high-transmittance film material greatly improves the transmittance of infrared light that could not pass through the screen. The infrared transmitter at the bottom of the screen emits infrared light. After the fingerprint is reflected, it penetrates the screen and shines on the fingerprint sensor to complete the fingerprint verification.

In theory, this technology could mean we see under-display fingerprint sensors on even cheaper smartphones, given the price difference between LCD and OLED. However, there’s no indication of how well this actually works yet, so I wouldn’t get too excited about it.

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