Touch Panel Frequency Filter for Unintended Hand Touches
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Touch panels with large touch-sensitive areas, such as tablet devices, struggle to accurately detect the position indicated by a finger or stylus when the edge of the hand, little finger side, or wrist comes into contact with the panel, leading to incorrect detection of touch inputs.
Innovation Solution
An input device and method that acquire touch intensity change signals and apply a frequency filter to suppress frequency components generated by non-finger or stylus touches, allowing for reliable detection of user input positions by filtering out unwanted touch signals from the edge of the hand or wrist.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If the touch-sensitive area is enlarged to accommodate larger display screens, then the display size and user interface area are improved, but the reliability of touch position detection deteriorates when the hand edge or wrist accidentally touches the panel
Solution Approach 1:
The patent applies frequency filtering to change the temporal parameter of touch intensity signals. By suppressing frequency components below a predetermined threshold, the system distinguishes between intentional finger touches (higher frequency) and accidental hand edge/wrist touches (lower frequency), thereby maintaining detection reliability across large touch-sensitive areas
Solution Approach 2:
The patent introduces a filter unit as an intermediary between the touch panel sensor and the position detection algorithm. This filter unit processes raw touch intensity change signals and outputs filtered signals that enable reliable position detection even when large areas are touched unintentionally
2Area of stationary object
If the touch-sensitive area is enlarged, then the display size and user interface area are improved, but the measurement precision of touch position deteriorates due to interference from hand edge or wrist touches
Solution Approach 1:
The patent changes the frequency parameter of touch signals through filtering. By removing low-frequency components characteristic of hand edge and wrist touches, the system preserves high-frequency components from intentional finger touches, thereby maintaining measurement precision across enlarged touch-sensitive areas
Solution Approach 2:
The patent applies frequency filtering selectively to different measuring positions on the touch panel. The filter unit processes signals at each measuring position independently, allowing the system to maintain precision at locations where finger touches occur while suppressing interference from hand edge contacts at border regions
Data Source
AI summary
A position indicated by a user with a finger or a stylus can be detected even in a case where an edge of a hand on a little finger side, a wrist or the like touches a touch panel. An input device acquires a touch intensity change signal that indicates a change of touch intensity at a plurality of measuring positions on a touch panel, applies a frequency filter, which suppresses a frequency component of the touch intensity change signal generated by a touch other than by a finger or a stylus, to the touch intensity change signal at at least one of the measuring positions, and generates data of a position indicated by a user on the touch panel based on the touch intensity change signal, to which the frequency filter is applied, at the respective measuring positions.