Touch panel for determining real coordinates of the multiple touch points and method thereof

摘要

A touch panel for determining real coordinates of multiple touch points is provided. The touch panel for determining real coordinates of multiple touch points comprises a sensing path layer having a plurality of first paths and a plurality of second paths for detecting the raw coordinates of said multiple touch points, and an Eliminating Path Layer having a plurality of third paths for eliminating ghost coordinates of said multiple touch points from said raw coordinates to output said real coordinates of said multiple touch points. The method of determining real coordinates of multiple touch points on the touch panel is also provided.

主权项

1. A method of determining real coordinates of multiple touch points, comprising steps of:
(a) scanning a plurality of first paths in a first direction and a plurality of second paths in a second direction of a sensing path layer when at least two touch points appear on a surface of a touch device and shorting and connecting a plurality of third paths in a third direction of an Eliminating Path Layer to ground; (b) computing centroids of changes in self capacitances corresponding to said touch points in both said first direction and said second direction, and calculating raw coordinates of said touch points by intersecting said centroids; (c) scanning said plurality of third paths when at least two said centroids are computed in both said first direction and said second direction in said step (b); (d) computing projections of said touch points in said third direction; (e) calculating projections of said raw coordinates of said touch points in said third direction; (f) comparing a distance between each said projections of said touch points and each said projections of said raw coordinates of said touch points with a threshold value; and (g) outputting said raw coordinates of said touch points as real coordinates of said touch points, if said distance is smaller than said threshold value in said step (f).