Miniatured and Wearable Photoacoustic Sensing System for Blood Pressure Monitoring

Cuffless continuous blood pressure monitoring is highly desirable in both healthcare and wearable electronics. Photoacoustic technology, with its superior selectivity for blood vessels, generates signals that include vessel diameter information, which can be used to estimate blood pressure. This paper presents the optimization of system parameters and the development of a miniatured, high-efficiency photoacoustic system utilizing a high-power VCSEL and an ultrasonic transducer. The system successfully detected different phantoms with depth information (7-11 mm), and size information (0.5 mm and 0.7 mm in diameter), demonstrating its potential for practical blood pressure measurements. Additionally, the effects of absorber dimensions and absorption coefficients on the photoacoustic signal are analyzed. This study highlights the importance of VC-SEL technology, ultrasonic transducers, and system parameter optimization in achieving a miniaturized, precise photoacoustic system for wearable blood pressure monitoring.