Fenix 6 Pro - pulse oximeter - infrared or just red light

Just curious if anyone knows that the red light emitted during pulse ox measurements is just ordinary red light or an infrared light?

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NickC4 over 5 years ago in reply to Crispin_Ellisdon +4 suggested

Just put Fenix 6 on a spectrometer. Quick and dirty 100ms snapshot. I put the watch in pulse Ox measure mode and was lucky to catch three wavelegths in one read. You can see the green (around 540 nm),…
Ian over 5 years ago in reply to 3811409 +1

3811409 said:
however what is used by Garmin's sensor?

According to the Garmin page I linked to and the text I copied and posted, "The level of oxygen contained in hemoglobin affects our bloods absorption…
Crispin_Ellisdon over 5 years ago +1 suggested

It's both red and infra red according to this official Garmin support article for the Vivosmart 4 https://support.garmin.com/en-GB/?faq=SK2Y9a9aBp5D6n4sXmPBG7 "...uses a combination of red and infrared…

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0 Ian over 5 years ago

I found a page on the Garmin India web site that gives some details on the Pulse Ox sensor found in the Fenix 5X Plus. I would expect the 6 to be the same. See here: Pulse Oximetry Functionality

From the page:

Our blood's hemoglobin is key to accurately detecting blood oxygen saturation. The level of oxygen contained in hemoglobin affects our bloods absorption of red and infrared light rays. By emitting light at these two frequencies, sensors on wearable devices can detect pulse data. Using this data, Garmin's specialised algorithms are able to calculate an estimate of the user's blood oxygen saturation.

What's odd is I found a similar page on the Garmin Malaysia site, but I can't seem to locate the page on the US site.

*shrug*

0 3811409 over 5 years ago in reply to Ian

yeah red or infrared is commonly used for pulse ox.. however what is used by Garmin's sensor?

0 Ian over 5 years ago in reply to 3811409

3811409 said:
however what is used by Garmin's sensor?

According to the Garmin page I linked to and the text I copied and posted, "The level of oxygen contained in hemoglobin affects our bloods absorption of red and infrared light rays. By emitting light at these two frequencies, sensors on wearable devices can detect pulse data."

I take that to mean that Garmin's Pulse Ox sensor uses both red and infrared LEDs.

0 Crispin_Ellisdon over 5 years ago

It's both red and infra red according to this official Garmin support article for the Vivosmart 4 https://support.garmin.com/en-GB/?faq=SK2Y9a9aBp5D6n4sXmPBG7 "...uses a combination of red and infrared lights with sensors on the back of the device which can determine the percentage of oxygenated blood (SpO2%) available in your blood."

Edit: A more generic Garmin support article is here https://support.garmin.com/en-GB/?faq=TMmlY0Pmik2Y9oG9CbMW16 but says the same thing.

0 NickC4 over 5 years ago in reply to Crispin_Ellisdon

Just put Fenix 6 on a spectrometer. Quick and dirty 100ms snapshot. I put the watch in pulse Ox measure mode and was lucky to catch three wavelegths in one read. You can see the green (around 540 nm), the big red peak (~ 650 nm) and some infrared (~930 nm). Don't read anything into peak heights, I was not careful about which LED I was centered on, or when I pressed go.

Nick.

0 3811409 over 5 years ago in reply to NickC4

wow great information... thanks a lot for sharing.. does this mean that red (middle) has the maximum intensity?

0 NickC4 over 5 years ago in reply to 3811409

No I was not careful enough that you can to take any information at all from the heights of the different wavelengths. It could be that the green was just turning off when I pressed scan, or the spec fibre was pointing more towards the red led.