A Methodology for Evaluating Accuracy of Capacitive Touch Sensing Grid Patterns

In recent years, there has been significant increase in research conducted in the field of capacitive touch technology. Capacitive touch screen technology, both in consumer electronics (for example, smartphones, MP3 players, etc.) and in wall mount displays (for example, ATM kiosks) seem to be omnipresent in the future. This paper discusses the physical design of the self-capacitive grid patterns used in current smartphones and the interpolation algorithms used to determine the position of the touch. The main aim of this paper is to simulate and test different touch screen patterns other than the widely used diamond shaped grid design and to provide a methodology for the accuracy comparison of sensor patterns. The paper deals with self-capacitance and presents results based on simulations for various sensor patterns.