Patent ID: 8420958

Claim:
A position method of a touch device, wherein the touch device has a plurality of scan lines, the position method comprising: sensing a plurality of capacitances in the scan lines; selecting the capacitances respectively sensed in an i th scan line of the scan lines and a subset of the scan lines neighboring with the i th scan line; determining the capacitance sensed in the i th scan line is a peak capacitance when the capacitance sensed in the i th scan line is larger than each of the capacitances sensed in the subset of the scan lines; and calculating a touch position according to the peak capacitance and the capacitances sensed in the subset of the scan lines, comprising: respectively calculating an i th length, an (i+1) th length, and an (i−1) th length according to the peak capacitance, an (i+1) th capacitance sensed in the subset of the scan lines, and an (i−1) th capacitance sensed in the subset of the scan lines; and calculating a first weighted sum of the i th length and a sub-length as the touch position when the i th length is smaller than a weighted value of the sub-length and a reference coefficient, wherein the sub-length is a maximum of the (i−1) th length and the (i+1) th length.