Intro story: I spent way too much time in the hospital with my newborn over the last weeks. Now he's home so all good. As I was in the hospital I noted SpO2 monitor connected to his foot. These run on a long cable to a head-unit, which is a clever device. The sensor itself is a disposable unit, which (with permission) I took.
To my knowledge principle is simple: IR + Red led + a photo-diode.
After a small disassembly I noted that there are few elements I did not expect / understand.
Cable is set up as follows:
- external shielding / silver color
- red/black power for diode(s) in said shielding
- another white cable which after stripping down has:
Red/black wired LED - I guess it has Red + IR build in
Green/White - photo diode?
Photo diode was wrapped in copper which was connected to 2 separate shielding
i think the most popular brand contains a UART connection, or something like that. But I dont know how to use it.
Thanks. The paper I read explained just that and some math behind it. I am curious about the engineering part of the sensor I got now as well. I see that my last night post does not have the pictures and the full text. I will update it later on!