Touch Sensor Bridge Electrode Auxiliary Mesh Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Touch sensors integrated into display devices often degrade image quality due to visible sensing electrodes and require improved optical and electrical properties for high-resolution and high-sensitivity touch sensing.
Innovation Solution
A touch sensor design featuring a bridge electrode surrounded by auxiliary electrodes with a mesh shape, etched regions, and a multi-layered structure of transparent conductive oxide and metal, which reduces channel resistance and suppresses parasitic capacitance, while the auxiliary electrodes shift the optical environment to high-frequency components, minimizing visual recognition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If sensing electrodes are formed using metal conductive material, then electrical conductivity and touch sensing sensitivity are improved, but visual visibility increases and image quality deteriorates
Solution Approach 1:
The sensing electrodes are constructed using a composite material system consisting of a transparent conductive oxide layer (such as ITO, IZO, or ZnO) combined with a metal layer. This composite structure provides both high electrical conductivity through the metal component and high transparency to minimize visual visibility, thereby resolving the contradiction between touch sensing sensitivity and electrode visibility.
Solution Approach 2:
The patent optimizes the thickness parameters of the transparent conductive oxide layer and metal layer to achieve the desired balance. By controlling the thickness of each layer, the electrodes maintain sufficient electrical conductivity for high-resolution touch sensing while remaining visually transparent to preserve image quality.
2Measurement precision
If sensing electrodes are made with lower channel resistance, then touch sensing resolution and sensitivity are improved, but optical properties deteriorate due to increased electrode material density
Solution Approach 1:
The multi-layer composite structure of transparent conductive oxide and metal allows achieving low channel resistance through the metal layer while maintaining optical transmission through the transparent conductive oxide layer. This resolves the contradiction between touch sensing resolution requiring low resistance and optical properties requiring minimal material density.
Data Source
AI summary
A touch sensor according to an embodiment of the present invention includes a base layer, a bridge electrode disposed on a top surface of the base layer, auxiliary electrodes disposed around the bridge electrode to be physically spaced apart from the bridge electrode, first sensing electrodes electrically connected to each other via the bridge electrode, and second sensing electrodes electrically separated from the first sensing electrodes and arranged in a direction different from an arrangement direction of the first sensing electrodes. A resistance may be decreased and a visual recognition of the bridge electrode may be suppressed using the auxiliary electrodes.