Touch Panel Parasitic Capacitance Reduction via Electrode Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Integrating touch electrodes into display panels often results in excessive parasitic capacitance, which affects the sensitivity of touch detection in touch devices.
Innovation Solution
A touch panel design where a portion of the conductive layer is used as a common electrode and another portion as a touch electrode, reducing the area of the touch electrode and thereby minimizing parasitic capacitance, while maintaining the ability to provide both touch and common voltage signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If touch electrodes are integrated into the display panel, then the overall thickness is reduced, but parasitic capacitance increases affecting touch detection sensitivity
Solution Approach 1:
The conductive layer is divided into multiple independent electrodes (first electrode, second electrode, third electrode) with different functions. The first electrode serves as touch electrode while the second and third electrodes serve as common electrodes, allowing spatial separation of touch detection function from common voltage provision, thereby reducing parasitic capacitance on the touch electrode.
Solution Approach 2:
Different regions of the conductive layer are assigned different electrical potentials and functions. The touch electrode region (first electrode) is electrically isolated from the common electrode regions (second and third electrodes) through insulating layers, creating local electrical independence that reduces parasitic capacitance while maintaining overall integration.
2Object-affected harmful factors
If the touch electrode area is reduced to minimize parasitic capacitance, then touch detection sensitivity improves, but the ability to provide common voltage signal may be affected
Solution Approach 1:
The second electrode and third electrode both serve as common electrodes that can provide common voltage signals. This multi-functionality ensures that even though the first electrode (touch electrode) has reduced area, the common voltage signal provision capability is maintained through the additional common electrodes.
Solution Approach 2:
The second electrode and third electrode are electrically connected through the fourth conductive layer, effectively merging their functions as common electrodes. This combination provides redundant common voltage signal paths, ensuring robust signal provision while allowing the touch electrode area to be minimized.
Data Source
AI summary
A touch panel includes a substrate, scan lines, data lines, sub-pixels, a first conductive line, a second conductive line, and a conductive layer. The sub-pixels are arranged in columns along a first direction and arranged in rows along a second direction. Each of the sub-pixels includes an active element and a pixel electrode electrically connected with the active element. The active element is electrically connected with a corresponding scan line and a corresponding data line. The conductive layer overlaps the sub-pixels. The conductive layer includes a first electrode and a second electrode. The first electrode is electrically connected with the first conductive line. The second electrode is electrically connected with the second conductive line. The second electrode is separated from the first electrode. One of the first electrode and the second electrode is a touch electrode, and another one is a common electrode.