Now Redmi demonstrates a solution to adding an in-display fingerprint reader to a phone with an LCD display. It is based on an innovative in-display fingerprint sensor that uses infrared light. In a video on Weibo (via Android Authority), the company’s general manager, Lu Weibing, has shown a working prototype of the technology, with the reader built into a regular backlit LCD screen of a Redmi Note8 Pro. A key component of the system is an infrared high-transmittance film material which allows the infrared light to pass through the screen without interfering with the backlight itself.

At this point, it is not clear how accurate and fast the system will actually be, and there’s no information whether any Redmi device will be equipped with this tech in 2020. In any case, using infrared light can bring in-display fingerprint sensors to low-end and middle-tier devices, most of which still use cheaper LCD screens.