The science of light-based sensing
Photoplethysmography (PPG) uses light to measure blood volume changes, enabling accurate heart rate and HRV monitoring without invasive procedures.
From light to insight
PPG technology captures the subtle changes in blood volume that occur with each heartbeat, providing the foundation for HRV analysis.
Light Emission
Green LED light (525nm wavelength) penetrates the skin surface to reach blood vessels.
Blood Volume Detection
As blood pulses through vessels, it absorbs different amounts of light with each heartbeat.
Signal Processing
A photodetector measures reflected light, creating a waveform that represents blood volume changes.
Beat-to-Beat Analysis
Advanced algorithms extract inter-beat intervals to calculate precise HRV metrics.
Clinical accuracy, consumer convenience
While ECG (electrocardiography) has been the gold standard for heart monitoring, PPG offers significant advantages for continuous, real-world health tracking.
Advantages of optical sensing
Non-Invasive
No skin contact with electrodes, no gel, no adhesives. Just comfortable optical sensing.
Continuous Monitoring
PPG enables 24/7 heart rate tracking without interrupting daily activities.
Wearable Friendly
Compact sensor design fits in watches, rings, and bands for comfortable wear.
Research Validated
Decades of clinical research support PPG accuracy for HRV measurement.