Proximity Edge Sensing

An electronic device, comprising:

• a cover glass;
• a first electrode;
• a second electrode;
• a first material positioned between the first and the second electrodes;
• a third electrode positioned on a side of the second electrode opposite the first electrode;
• and
• a second material positioned between the second electrode and the third electrode;
• wherein the electronic device is operable to:
• detect an applied force on a cover glass of an electronic device based on a first change in capacitance between the first electrode and the second electrode while the third electrode functions as a force sensing ground shield;
• detect a proximity of an object to the electronic device based on a second change in capacitance measured using the third electrode, while the first electrode functions as a proximity ground shield.

An electronic device, comprising:

• a housing;
• a cover glass positioned adjacent to the housing, the cover glass including:
• a cover glass surface having a display area;
• a cover glass edge surface;
• and
• a cavity formed partially in the cover glass opposite the cover glass surface apart from the display area;
• a touch sensing electrode positioned on the cover glass, opposite the cover glass surface in the display area and oriented toward the cover glass surface;
• and
• an additional electrode positioned in the cavity, oriented toward the cover glass edge surface;
• wherein:
• the touch sensing electrode is operable at least to detect a touch of an object on the cover glass surface;
• and
• a proximity of the object to the cover glass edge may be detected by a change in capacitance measured using the additional electrode.

A method of controlling a combined proximity and force sensor, comprising:

• operating the combined proximity and force sensor in a force sensing mode in which an applied force on a surface of an electronic device can be detected based on a first change in capacitance between a first electrode and a second electrode of the combined proximity and force sensor while a third electrode of the combined proximity and force sensor is used as a force sensing ground shield;
• operating the combined proximity and force sensor in a proximity sensing mode in which proximity of an object to the surface of the electronic device can be detected based on a second change in capacitance measured at the third electrode while the first electrode is used as a proximity sensing ground shield;
• and
• switching the combined proximity and force sensor between the proximity sensing mode and the force sensing mode.