As a reminder, Xiaomi Mi 11 turned out to be the first mobile phone that allows measuring heart rate through the screen. The CEO of Xiaomi Lei Jun has officially announced that the Xiaomi Mi 11 smartphone is not inferior to modern smartwatches in terms of pulse measurement accuracy.
Now details have appeared on this score. According to official figures, the heart rate measurement function is intelligently integrated into the sub-screen fingerprint scanner without adding additional equipment or increasing the thickness of the case.
The principle of the technology in Xiaomi Mi 11 is well thought out. An AMOLED display is used as a light source, and an optical fingerprint sensor acts as an information receiver. When the heart rate function is active, the light emitted from the screen hits the finger, and the optical fingerprint sensor detects changes in light intensity.
Xiaomi representatives point out that the amount of light that the screen emits is enough to measure the pulse, while the accuracy is very high. When the heart rate function is activated, the screen emits green light, which is easily absorbed by the human body, and the intensity of the reflected light varies greatly.
In terms of accuracy, tests carried out by the SGS laboratory showed that compared to professional pulse oximeters, the difference in the performance of the Xiaomi Mi 11 is about 2.11 beats per minute. In the case of most fitness bracelets and smartwatches, this difference is about 3 beats per minute.
(Via)