Method for determining the position of a contact on a touch panel and corresponding system

摘要

A method for determining the position of a contact on a panel envisages, during a detection operation, detecting vibration signals at a plurality of detection areas fixed with respect to the panel as a function of vibrations generated by the contact; determining detection values of temporal differences between times of detection of the vibrations at pairs of said detection areas; and determining the position of the contact as a function of said temporal differences. A characterization operation, preceding that of detection, envisages defining contact areas (key1-keyn) on the panel and associating to these contact areas respective ranges of admissible values for the temporal differences. In order to determine the position of the contact in a given contact area, the membership of the detection values of the temporal differences to the respective ranges of admissible values of the given contact area is verified. The method moreover envisages implementation of an algorithm for reconstruction and filtering of crossing signals, originated by the comparison of the vibration signals with one or more threshold values.

主权项

1. A method, comprising:
detecting signals at sensors; calculating a first duration between two first consecutive crossings of a threshold by a first signal; calculating a second duration between two second consecutive crossings of the threshold by the first signal, the two second consecutive crossings subsequent to the two first consecutive crossings; calculating a third duration between the last of the first consecutive crossings and the first of the second consecutive crossings; calculating a fourth duration between two first consecutive crossings of the threshold by a second signal; and identifying the first of the two second consecutive crossings as being suitable for use in a calculation in response to the first duration being smaller than the second and fourth durations and the third duration being greater than a smallest one of the first, second, and fourth durations.