Multi-touch points detection for capacitive touch panel

Abstract

We consider the detection of multiple touch points for capacitive touch panel systems under Gaussian noise. We propose an algorithm that reduces the noise-induced detection error and improves the detection accuracy with partial touch signal information. The proposed algorithm is based on the likelihood ratio test, and utilizes the touch signal features, such as the local maximum, the range of touch magnitude, and the consecutive occurrence of touch locations, to first detect touch points and then calculates the real touch coordinates based on the weighting average technique. Simulation demonstrates the improved performance of the proposed algorithm. © 2013 APSIPA.