US Patent 11772801 Electric field sensor with sensitivity-attenuating ground ring

An electric field sensor includes an insulating substrate, a plurality of electrodes, an insulator, a plurality vias, and a ground ring. The electrodes are disposed on the substrate. The insulator is disposed over the electrodes. The vias are coupled to the electrodes and extend through the substrate at a right angle to the electrodes. The ground ring is disposed around the electrodes and the vias and is configured to attenuate a sensitivity of the sensor to electric fields outwards of the ground ring.