A non-contact flexible pyroelectric sensor for wireless physiological monitoring system

Recently, human physiological information wireless monitoring in real-time is particularly important in health analysis. As a solution, a non-contact wireless physiological monitoring system based on pyroelectric generator (PyG), whose core part consists of a wireless circuit processing module and a polyvinylidene fluoride (PVDF) film, has been successfully designed. Owing to the temperature change under the stimulation of an external heat source, the output voltage of the PyG self-powered flexible sensor increases with the heat source temperature variation in the range of 295–355 K. Furthermore, based on the natural temperature oscillation between the living body and surrounding environment, the sensor can realize human physiological information assessment, for example, temperature monitoring of the palms, fingers, respiratory heat signals from mouth or nose or non-contact spatial heat mapping recognition of finger movement via sensor array. On this basis, a portable wireless monitoring system was designed by integrating the intelligent sensor with a signal conditioning circuit, data conversion storage module, Bluetooth module, and power module. This system can acquire real-time human oral or nasal breathing signals in the personal mobile app to evaluate the physiological state of individuals. Additionally, the wireless monitoring system can be activated within 10 m, demonstrating the application of PyG sensors in remote data transmission.