Photoplethysmography
The science of measuring blood pressure through light — how V-CHEK uses PPG sensors for painless, accurate vital sign monitoring.
Photoplethysmography uses light to detect blood volume changes in tissue
PPG is a non-invasive optical technique that uses red and green LED light sources to illuminate blood vessels beneath the skin. An optical sensor detects the amount of light absorbed or reflected by blood, creating a waveform that represents pulse and blood flow characteristics.
V-CHEK’s proprietary algorithms analyze these waveforms to determine systolic and diastolic blood pressure changes relative to a calibration reference point — all without physical compression.
Traditional Sphygmomanometer
- Painful physical occlusion of brachial artery
- Mercury column / gauge measurement at upper arm
- Requires cuff inflation and deflation cycle
- Arm compression causes discomfort
- Single snapshot measurement
V-CHEK Optical Blood Pressure Sensor
- Fingertip tissue measurement — zero compression
- Capillary network illuminated by red & green LEDs
- Optical sensor tracks vascular flow continuously
- Data tracking without painful pressure
- Non-compressed measurement zone
Red & Green LEDs
Dual-wavelength light sources illuminate fingertip tissue to capture vascular blood flow patterns.
Optical Sensor
High-sensitivity photodetector captures reflected light intensity changes corresponding to pulse waves.
Signal Processing
Advanced algorithms convert PPG waveforms into accurate BP, heart rate, and SpO₂ readings.