Touch Sensing Substrate Dummy Electrode Shielding
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Solution Overview
Problem
Conventional integrated capacitive touch sensing panels face issues with high noise-to-signal ratio due to parasitic capacitance between sensing series and the common electrode, leading to erroneous actions and reduced sensitivity.
Innovation Solution
Incorporation of dummy sensing series electrically insulated and potentially connected to the corresponding sensing series, which are placed above the sensing series and the common electrode, effectively reducing cross-talk by shielding the common electrode and sensing series.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the common electrode is disposed close to the sensing series to reduce panel thickness, then the panel thickness is reduced, but the parasitic capacitance between the common electrode and sensing series increases, leading to high noise and reduced sensitivity
Solution Approach 1:
The patent introduces a dummy sensing series as an intermediary element positioned between the common electrode and the actual sensing series. This dummy sensing series acts as a mediator that intercepts and redirects the electric field lines, preventing direct interaction between the common electrode and the sensing series, thereby reducing parasitic capacitance while maintaining the close-proximity configuration for thin panel design
2Speed
If the distance between the common electrode and sensing series is reduced to improve response speed, then the response speed is improved, but the parasitic capacitance increases, causing more erroneous actions
Solution Approach 1:
The dummy sensing series serves as an intermediary that allows the common electrode to be positioned close to the sensing series for fast response, while simultaneously preventing harmful parasitic capacitance effects. The dummy sensing series captures the electric field interaction, enabling close spacing without compromising measurement accuracy or increasing erroneous actions
3Device complexity
If the sensing series are disposed at the same side of the substrate to simplify structure, then the structure is simplified, but the parasitic capacitance between common electrode and sensing series cannot be neglected, reducing signal-to-noise ratio
Solution Approach 1:
By introducing the dummy sensing series as an intermediary element on the same side of the substrate, the patent maintains the simplified single-side structure while effectively reducing parasitic capacitance. The dummy sensing series intercepts electric field lines between the common electrode and actual sensing series, preserving the favorable structural simplicity without sacrificing signal-to-noise ratio
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Significantly improves the signal-to-noise ratio and sensitivity of the touch sensing substrate by minimizing parasitic capacitance and noise interference, thereby reducing erroneous actions and enhancing overall performance.
Implementation Method 1
the first dummy sensing series are electrically insulated from each other, and each of the first dummy sensing series and corresponding one of the first sensing series have the same potential
Data Source
AI summary
A touch sensing substrate includes a substrate, first and second sensing series, a first dielectric layer, first and second dummy sensing series, a second dielectric layer, and a common electrode. The first sensing series are electrically insulated from each other, and so are the second sensing series. The first and the second sensing series are covered by the first dielectric layer. The first and the second dummy sensing series are disposed on the first dielectric layer. The first and the second dummy sensing series are disposed above the first and the second sensing series, respectively, and the dummy sensing series and the sensing series corresponding thereto have the same potential. The first and the second dummy sensing series are covered by the second dielectric layer. The common electrode is disposed on the second dielectric layer. A touch sensing liquid crystal display having the above-mentioned touch sensing substrate is also provided.