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A Look Inside An Optical Pulse Meter

🕑 Added 2024-04-21 22:11:44 +0000 UTC

Comments

Joel Murphy

I like that LED light guides! Def gonna try to 3d print something to do that. Likely won't as high resolution, but worth the try. The BPM and blood ox calculations aren't that hard. hey multiplex a red and a (near) infrared LED to measure the intensity of received light at the sensor. Hemoglobin in the blood absorbs the infrared light differently when it is saturated (with oxygen, we hope!) than when it is not saturated. I think the math involves some kind of ratio...?

Tara Daves

Fascinating! Just a tiny chip drives the sensor, counters, and display

Zygmunt Dean

Good to see your sats at that level Fran, back in February mine were down to 88 for a while. 😵

Zygmunt Dean

A prying chisel - "Well, if you must pry..." "I must! I must!"

adorfer

I was not aware that those are still made, since the same for factor with oled and O2 saturation ist just 15 buvks too

Jon (0ryn) Westgate

Interesting to see that the bar-o-graph LEDs were going twice as fast as they should. I have a Garmin watch that I use to track my pulse and that often gets confused and will show my pulse and double it's real rate. It's rather annoying because it was an expensive watch.

Motten

It's fun to see useful little gadgets like this. Quite impressive that it's able to measure blood oxygen levels in that way. Thanks for the mini teardown. And hooray for beta blockers, I'm glad you're okay, Fran.