Sleep & HRV tracking · RingConn
RingConn Gen 3
A smart ring reads your pulse through the finger with light, plus skin temperature and movement, then turns overnight trends into sleep and recovery scores.
Callout
Optical sensors
LEDs shine into the finger; a photodiode reads tiny changes in reflected light with each pulse. That gives heart rate, HRV and blood-oxygen estimates.
The science: Ring trackers agree well with lab sleep tests on total sleep time but are weaker on individual sleep stages (de Zambotti et al., 2017). Use for trends, not diagnosis.