Touch Position Analysis Using Zero-Crossing Segmentation

The patent segments the touch detection process into multiple stages: first identifying zero-crossing points in the sensing signal, then performing peak detection within segments defined by these zero-crossings. This segmentation allows the system to handle multiple close touches by treating each segment independently, thereby maintaining measurement precision without requiring excessively complex global threshold determination.

The patent performs preliminary zero-crossing detection before peak detection. By first identifying where the sensing signal crosses zero, the system prepares segmented regions where subsequent peak detection can be performed more accurately. This preliminary action enables better separation of multiple touches that would otherwise be difficult to distinguish with a single threshold approach.

Instead of directly analyzing peak values in the sensing signal, the patent inverts the approach by first analyzing zero-crossing points and then using these to guide peak detection. This inversion transforms the problem from directly interpreting overlapping signal peaks to using zero-crossings as reliable anchors that define search regions for peaks, thereby improving reliability when touch paths cross.

The patent introduces zero-crossing points as an intermediary element between the raw sensing signal and the final touch position determination. These zero-crossings serve as mediators that divide the sensing signal into manageable segments, allowing peak detection to proceed more reliably even when multiple touches overlap, thus improving detection accuracy without excessive complexity.

The patent performs preliminary zero-crossing detection to establish segmented regions, but does not directly equate the number of zero-crossings with the number of touches. Instead, it uses these segments as search spaces for subsequent peak detection, where actual touch points are identified. This preliminary segmentation without direct equivalence allows accurate touch counting even when the relationship between zero-crossings and touches is not one-to-one.

The patent segments the sensing signal using zero-crossings but then performs independent peak detection within each segment. This segmentation approach allows the system to handle cases where multiple touches may produce fewer zero-crossings or where single touches may produce multiple zero-crossings, thereby maintaining accurate touch counting by focusing on peak detection within segments rather than simply counting zero-crossings.