A Novel Technology for Continuous Breathing Monitoring during Sleep without Wearing a Sensor

Breathing pattern and its variation during sleep is clinically important regarding the functionality of the cardiac- and the respiratory systems. There is an increasing need for an inexpensive sensor that can provide continuous and high-quality breathing signal during sleep without wearing a sensor, or feeling its presence. This novel technology is based on constructing a flexible capacitor made of two flexible and conductive structures, having surfaces coated with a thin and flexible insolating layer. These structures are shaped in a way that forms multiple contact regions, where each contact area forms a pressure-sensitive capacitor. The overall capacitance increases sensitively with pressure with controlled linear or nonlinear characteristics. Capacitance can be converted into analogue or digital signal by standard methods. A pad placed over a mattress that includes an array of such sensors was demonstrated to provide high-quality breathing patterns under different body postures.