The applications of projected capacitive array sensing in healthcare

This paper presents a cost-effective sensor system for the applications of large area array sensing. Unlike the traditional pressure sensing methods, projected capacitor technologies are proposed for sensing. The rapid charge time method is utilized to measure the capacitance values of the projected capacitive array electrodes. By constructing the process of projected capacitive array electrode, the required characteristics of the projected capacitor are identified, especially characteristics for large area applications. Three main factors, the area of electrodes, the use of shielding and gap between the guard ring and the electrode, also affect the capacitance primary value especially in the large-size applications. At last, a flexible projected capacitive sensing array with 8 × 10 electrodes was implemented to validate the feasibility of projected capacitive array electrodes.