US Patent 10474194 Wearable electronic device with an inductive user interface

A wearable electronic device comprises a housing, a pushbutton, a sensor, and a processing element. The housing includes a sealed internal cavity formed in part by a bottom wall and a side wall. The pushbutton is coupled to an outer surface of the side wall and includes a plunger configured to move in relation to the side wall when the pushbutton is pushed. The sensor is positioned in the internal cavity adjacent to an inner surface of the side wall and includes a conductive element through which an electronic signal is operable to flow. The sensor is configured to modify an electrical characteristic of the electronic signal according to a distance between the plunger and the conductive element. The processing element is configured to receive the electronic signal from the sensor and to process the electronic signal to determine when the pushbutton is pushed.