During the use of the bracelet, the back of the bracelet often glows green from time to time, or when we switch to the heart rate interface test at the end of the bracelet, the bottom of the bracelet will also begin to flash green.
The background has received some user consultation:
What is the use of this green light?
Can I turn it off?
Will this green light be harmful and radiate?
Why is my heart rate test failing?
Today, the heart rate monitors the light used in a more straightforward perspective.
1.Why is it flashing green?
That’s because Gavage’s smart bracelets and watches use PhotoPlethysmoGraphy to monitor heart rate, or PPG.
Their distinguishing feature is that the sensor area is equipped with a green LED light. When you turn on the “Heart Rate Auto-Monitoring” function switch in the WoFit Assistant or H Band APP, the bracelet will measure your heart rate periodically and automatically for 24 hours.
The principle is simple: the blood is red, reflecting red light and absorbing green light. The green LED lamp is used in conjunction with the photoelectric sensor to emit green light into the blood vessel to detect the amount of blood flowing through the wrist for 24 hours, thereby obtaining heart rate information according to the change in light intensity.
and so,The green light behind the bracelet is the heart rate monitoring function!
When the green light is not flashing, you may notice,The back of the bracelet is like this, the inside of the ring is a square inside the transparent,The heart rate sensor.
Let’s take a very close to life example. You open the phone camera, cover the phone camera with your finger, and use the strong light (if the phone camera and flash are close to the flash), you can see the image is flickering. Dark, can be understood as corresponding to the heartbeat.
2.Why not red light or other colors of light?
Because in the blood of this red liquid, the absorption rate of green light is the largest, the data is relatively accurate, to achieve the minimum loss and interference.
When the user’s heart beats, more blood will flow through the user’s wrist, and the amount of green light will be absorbed. In the heartbeat gap, blood flow is reduced, resulting in a decrease in green light absorption.
3.Sometimes it will flash when I sleep at night, can I not let it flash?
If you don’t want it to light up, you can turn off the Automatic Heart Rate Monitor on the WoFit Assistant or H Band App. However, for your health, you can collect more health data, do you really want to do this?
4.What factors affect the heart rate test results?
Non-standard wearing methods can affect the measurement of heart rate signals, such as light leakage caused by incomplete fitting, loose wearing of the wristband, and slight movement of the bracelet on the skin.
In addition, the arm swings, clenched fists or irregular movements, like the pendulum swings, the centrifugal force will also cause a large change in blood volume. When vasoconstriction and centrifugal force interact in the blood, it is more difficult to distinguish the blood volume in the blood vessel, which may affect the heart rate signal.
The right way to measure: Place your arms flat, relax and stay still while keeping your wrists close to your arms.
Have you ever seen the news that the black brothers can’t measure the heart rate?
The color of our skin is mainly caused by melanin, which shows different skin tones depending on the melanin content. Melanin has a high absorption rate for green light. If the skin color is very dark, the emitted green light absorbs almost, and the reflected light is very weak, so it is difficult to measure the effective PPG. This will not be elaborated.
Similarly, when worn correctly, some people have tattoos, scars, sweat and other individual differences that can cause heart rate measurement to not work properly.
5.Why does my heart rate manual test fail?
When measuring the heart rate, be careful to keep the person at rest and keep the bottom of the bracelet close to the arm without leaving a clear gap. Do not shake the arm during the measurement.
6.Is this light harmful to the human body?
The hand ring measures the heart rate. The green light source belongs to the visible light. It is not different from the natural green light and is harmless to the human skin. The monitoring method is only collected by illuminating, so there is no harm.