Hover Position Calculation in a Touchscreen Device

摘要

A method calculates the position of a conductive object hovering above a plurality of mutual capacitance sensors, where each mutual capacitance sensor is represented as a unit cell in an array of unit cells. The method measures the capacitance of each sensor. The method identifies a peak unit cell based on the measured capacitances and calculates an edge cutoff value. A plurality of unit cells with measured capacitances within a range defined by the edge cutoff value are selected and the position of the hovering object is calculated. In some embodiments, the array comprises a first plurality of capacitance sensing electrodes disposed along a first axis and a second plurality of capacitance sensing electrodes disposed along a second axis. In some embodiments, the array and a controller form a user interface device, and the controller is configured to calculate the position of the conductive object using the method described above.

主权项

1. A method comprising:
measuring capacitance on a plurality of mutual capacitance sensors, each mutual capacitance sensor represented as a unit cell in an array of unit cells; identifying a peak unit cell based on the measured capacitances; calculating an edge cutoff value from the measured capacitances; selecting a plurality of unit cells with measured capacitance within a range defined by the edge cutoff value; and calculating a position of a conductive object hovering above the plurality of mutual capacitance sensors based on the measured capacitances within a region defined by the edge cutoff value.