Redmi General Manager, Lu Weibing today announced that the company has successfully implemented LCD Fingerprint scanning on an LCD screen. At present, all LCD screen mobile phones only use physical fingerprint sensor on the back or the side. The Redmi R&D team has now overcome this problem with a new method and in-screen fingerprint on LCD screens is also ready for mass production, said the company.
The working principle of the screen fingerprint is simply to record the characteristics of the fingerprint and feed it back to the sensor below the screen to determine whether it coincides with the fingerprint that had already been registered.
However, because the fingerprint sensor is below the screen, there needs to be a channel to transmit optical or ultrasonic signals, which results in the current implementation only on OLED screens. LCD screens can’t feature this visible unlocking method because of the backlight module.
In the new and innovative method Redmi has used infrared high-transmittance material that greatly improves the transmittance of infrared light. 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, which solves the LCD Fingerprint problem.
The company has also demoed it on a Redmi Note 8 Pro prototype after replacing the screen with the new LCD screen that has an in-display fingerprint scanner. As you can see, the fingerprint recognition looks as fast as an OLED screen, however the fingerprint sensor is present closer to the bottom bezel of the screen. We will have to wait to see how this compares to the in-display fingerprint scanning on an OLED display.