Geometry Optimization to Enhance the Range of Detection of Fringing Field-Based Capacitive Proximity Sensors

Fringe field-based capacitive proximity sensors are well-suited to detect the presence of both conducting and non-conducting objects. The configuration of electrodes within these sensors significantly influences the fringe field, thus impacting the detection range. This research focuses on optimizing electrode geometry to enhance the fringe field in proximity sensors. Analytical modeling is utilized to identify the geometry that yields the most extensive fringing field, and this is subsequently verified using finite element modeling. To validate the findings from analytical and finite element modeling, fringe filed-based capacitive proximity sensors were fabricated on FR4 substrates and tested using a custom-designed setup. The characterization results closely align with the conclusions drawn from the analytical and finite element modeling.