System and method for detecting locations of touches on a touch sensor

摘要

A projected capacitive touch sensor system includes a substrate that defines a plurality of non-overlapping areas. Each non-overlapping area includes a plurality of detection electrodes arranged in non-overlapping columns. The columns include a horizontal detection electrode that extends along substantially an entire height of a first column, and at least a second column of at least two vertical detection electrodes that are electrically isolated from one another. The system further includes a measuring circuit configured to measure a mutual capacitance between the horizontal detection electrode and each of the at least two vertical detection electrodes in a given area. A processing logic circuit of the system is configured to determine horizontal detection electrode and vertical detection electrode combinations that have a changed mutual capacitance. The processing logic is also configured to determine the touch location based on a location of the determined horizontal detection electrode and vertical electrode combinations.

主权项

1. A method for determining a touch location of a projected capacitive touch sensor, comprising:
providing a substrate with a plurality of non-overlapping areas, wherein each non-overlapping area includes a horizontal detection electrode in a first column and a second column with a plurality of vertical detection electrodes; measuring a first mutual capacitance between the horizontal detection electrode and a vertical detection electrode from the plurality of vertical detection electrodes; measuring a second mutual capacitance between the horizontal detection electrode and another vertical detection electrode from the plurality of vertical detection electrodes; determining one or more horizontal detection electrode and vertical detection electrode combinations based on a change in the first mutual capacitance and the second mutual capacitance; determining a digitized capacitance value based on the change in the first and the second mutual capacitances; and determining the touch location based on a location of the one or more determined horizontal detection electrode and vertical electrode combinations and the digital capacitance value.