Stretchable PPG sensor with light polarization for physical activity–permissible monitoring

Abstract

Skin-attachable sensors, which represent the ultimate form of wearable electronic devices that ensure conformal contact with skin, suffer from motion artifact limitations owing to relative changes in position between the sensor and skin during physical activities. In this study, a polarization-selective structure of a skin-conformable photoplethysmographic (PPG) sensor was developed to decrease the amount of scattered light from the epidermis, which is the main cause of motion artifacts. The motion artifacts were suppressed more than 10-fold in comparison with those of rigid sensors. The developed sensor—with two orthogonal polarizers—facilitated successful PPG signal monitoring during wrist angle movements corresponding to high levels of physical activity, enabling continuous monitoring of daily activities, even while exercising for personal health care.

Evolution of nanostructured skin patches towards multifunctional wearable platforms for biomedical applications

“…Electronic skin patches with multiple functions require the integration of numerous electronic/sensing components on conformal and soft substrates. This is attributed to the growing trend of high-quality requirements of electrostimulation therapies and real-time physiological signals detections, 28,253–255 consequently leading to a higher demand for power supply. Electronic skin patches rely heavily on external power supply units, especially bulky batteries, to meet the power consumption requirements, which severely hampers the portability and feasibility of skin patch systems.…”

Recent advances in skin-like wearable sensors: sensor design, health monitoring, and intelligent auxiliary

“…12 Therefore, care should be Sensors & Diagnostics Tutorial review taken when using wrist band optical sensors to monitor realtime heart rate during aerobic exercise. 50 Lee et al 155 developed a skin-attachable PPG sensor with an orthogonal polarizer-analyzer (OPA) pair to reduce the amount of scattered light from the epidermis, which is the main cause of motion artifacts. The schematic diagram of the OPA sensor is shown in Fig.…”

“…Lee et al 155 developed a skin-attachable PPG sensor with an orthogonal polarizer-analyzer (OPA) pair to reduce the amount of scattered light from the epidermis, which is the main cause of motion artifacts. The schematic diagram of the OPA sensor is shown in Fig.…”

Wavelength and Polarization Sensitive Synaptic Phototransistor Based on Organic n-type Semiconductor/Supramolecular J-Aggregate Heterostructure

“…1 Light can include both scalar (e.g., wavelength and intensity) as well as vector (e.g., linear and circular polarity) information, 2 suggesting that the more we can finely discriminate this spectropolarimetric information, the greater the amount of visual information we can acquire of our environment. Several photodetecting systems that can recognize a specific wavelength and polarity of light have been developed for application in future technology such as hyperspectral imaging, 3 biomedical imaging, 4 security and surveillance, 5 spectral analysis, 6 and polarization-perceptual neuromorphic vision. 7 However, most photodetectors require additional optical filters to detect a specific color or a specific polarization, which thus hampers the development of compact high resolution devices.…”