Optical PPG Bio-Sensors
FITVII smartwatches utilize multi-channel green and infrared light-emitting diodes (LEDs) coupled with high-sensitivity photodetectors. As blood surges through radial micro-vessels with every cardiac contraction, light absorption fluctuates. Proprietary algorithms translate these optical waveform changes into estimated systolic and diastolic pressure trends.
Requires baseline calibration against an upper-arm cuff.