Publication in Sensors: A Hybrid Photoplethysmography (PPG) Sensor System Design for Heart Rate Monitoring

Thanks to the great collaboration with Prof, Hattori’s lab in Kyushu University, we have recently reported in Sensors on a Hybrid photoplethysmography (PPG) sensor system designed for heart rate monitoring. Here, we reveal that combination of an inorganic light-emitting diode (LED) and a circular-shaped organic photodetector (OPD) surrounding the LED for efficient light harvest followed by the proper driving circuit for accurate PPG signal acquisition.

This study demonstrated that the hybrid PPG sensor, incorporating an optimized OPD structure, is a promising solution for low-power heart rate monitoring. For some more details, see our ACTIVITIES site.

The performance of the hybrid sensor system was confirmed by the heart rate detection process from the PPG using fast Fourier transform analysis. The PPG signal obtained with a 50% LED duty cycle and 250 Hz sampling rate resulted in accurate heart rate monitoring with an acceptable range of error. The effects of the LED duty cycle and the LED luminous intensity were found to be crucial to the heart rate accuracy and to the power consumption, i.e., indispensable factors for the hybrid sensor.