If you’ve used the Oura Ring, you would definitely have noticed it emitting lights. Green and red, to be specific. Ever wondered what’s the purpose of these? Why do the smart rings need a light? And why red and green?
Let’s break down the science behind these.
What Does the Green Light Mean on the Oura Ring?
The sensors turn on the green light on the Oura Ring Gen 3 when tracking heart rate during the daytime. This includes tracking Live Heart Rate, Daytime Heart Rate, and Workout Heart Rate.
The Oura Ring tracks my heart rate every 5 minutes and allows me to check my heart rate on-demand. The heart rate during my workout is also tracked with the help of the green LED on the Oura Gen 3.
This Is How The Green Light Works on the Oura Gen 3
The green LEDs enable the ring to take these measurements using the PPG (photoplethysmography) technology at a 50Hz frequency. The PPG tech shines a light onto the skin which reaches blood vessels. Some of this light is reflected on a photodetector, and by measuring the intensity of this reflected light using a waveform, the amount of blood in the blood vessel is captured.
Different metrics are captured using different colored lights and their unique frequency. Just like more green light is absorbed by blood vessels when they are expanded, which allows the pulse rate to be measured accurately.
Similarly, when the ring records workout heart rate during activity, the continuous movement can hinder the accuracy of the results. Therefore, to compensate, the Oura Ring increases the sampling rate of the green LEDs.
Although the green LEDs are only emitted during the daytime, according to Oura, I have also noticed them at night when I’m awake. So, I believe it’s a matter of movement and other metrics that tell the ring whether I am sleeping or awake, based on which it emits the right LED.
What Does the Red Light Mean on the Oura Ring?
The red LED, along with the infrared LED on the Oura Gen 3, is emitted to measure blood oxygen (SpO2) during sleep. The occasional glow of the red LED during the day when I’m awake is only when I’m resting or taking a nap and there has been no movement for a certain amount of time.
The same concept of light being sent into the blood vessels and reflected back by the PPG technology is used for accurate blood oxygen sensing. Oxygen-rich blood reflects more red light, and oxygen-poor blood reflects more infrared light.
Unlike the green LED, which is emitted every 5 minutes to track heart rate or goes on when I ask for an on-spot measurement for my live heart rate, the red LED is always on during sleep to capture SpO2 data continuously.
Can the LED Lights Affect the Battery Life of My Oura Ring?
The tracking of certain metrics requires more signal and battery, which affects the battery life of the Oura Ring. The Live Heart Rate requires a stronger signal; therefore, the green LEDs affect the battery life when this metric is measured more frequently.
Similarly, the blood oxygen sensing feature, which uses red and infrared LEDs, is also related to significant battery drainage. Here are a few tips to optimize your Oura Ring’s battery life so that you can use it in all its glory.
FAQs
Wrap Up
With the use of advanced PPG technology, the Oura Ring emits lights onto the skin to track various measures. Now that we know what the green and red LEDs are used for, it has taken out the mystery behind the glowing lights.
With this understanding, we can now manage our Oura Ring’s performance better and make the most out of its battery life and our health metrics, of course.
