Organic Photoplethysmography Sensors for Wearable Health Monitoring

Abstract The increasing emphasis on health and wellness has spurred developments in wearable health technologies, particularly in photoplethysmography (PPG) technology. This technology is notable for its noninvasive method of measuring physiological parameters, especially cardiovascular health. Conventional PPG sensors typically use rigid inorganic materials; however, organic PPG sensors present a viable alternative. These sensors are distinguished by their flexibility and biocompatibility, which enhance skin conformity and reduce motion artifacts, thereby increasing both accuracy and comfort for wearable applications. This review examines the core principles of organic PPG sensors and underscores their distinct advantages over conventional inorganic counterparts. It further discusses recent progress in device design and signal processing techniques that are designed to optimize the performance of organic PPG sensors. Additionally, this review covers the broad applications of organic PPG sensors in monitoring heart rate, measuring blood oxygen saturation, and estimating blood pressure. Finally, this article evaluates the challenges and future prospects of this promising technology, emphasizing its potential to transform wearable health monitoring.