Appearance contrast:
1. The figure below is the change of the charger. Due to the addition of Electrocardiographic sensor at the bottom of the band body, the corresponding charger has been specially adapted.It cannot be adapted to the previous charger.
2. The green light as shown in the figure below will be emitted when the band detects the heart rate when unpacking the box picture of Mi band.
The photoelectric type measures heart rate mainly through light reflection: it shoots a beam of light onto the wrist and uses a camera to observe the reflected shadow, based on the principle that when the heart beats, the blood vessels of the whole body will have slight fluctuations.If there is a small change, the heart is considered to beat once.Blood is red. It reflects red light and absorbs green light.The Mi band uses green LED lights and light-sensitive diodes to monitor the amount of blood flowing through the wrist.As the heart beats, blood flows through the wrist and the green light is absorbed.In addition, different skin colors absorb light differently, so each skin color is characterized by a different light absorption pattern. Dark skin absorbs more green light, which also indicates why most devices use green LED as light emitter.
