Touchscreen Electrode Arrangement with Varying Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing touchscreen technologies face challenges in reducing the number of layers and wiring complexity while maintaining high touch resolution and accuracy, which increases costs and complicates production, and can result in visible interference patterns and reduced optical properties.
Innovation Solution
A touchscreen assembly with an array of electrode elements that vary in density to create a sensing gradient, allowing the position of an input to be determined by the proportion of elements, eliminating the need for resistive material coupling and reducing the number of layers and wiring connections.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple layers of transparent conductors are used to form electrode arrays, then touch sensing capability is improved, but visibility deteriorates due to visible interference and moiré patterns
Solution Approach 1:
The patent extracts the resistive material coupling layer from the traditional multi-layer touchscreen structure, eliminating the source of visible interference patterns while preserving the electrode array functionality through direct wiring connections
Solution Approach 2:
The patent employs asymmetric electrode patterns where electrode elements are intentionally positioned at non-uniform intervals and with varying orientations, disrupting the formation of symmetric moiré patterns and improving visual appearance
2Measurement precision
If complex patterns of touchscreen elements are used to improve touch resolution, then measurement precision is improved, but device complexity increases due to more complex routing of connecting lines
Solution Approach 1:
The patent segments the electrode array into multiple independent groups with distinct wiring paths, allowing complex electrode patterns to be managed through modular connections rather than a single complex routing system
Solution Approach 2:
The patent resolves wiring complexity by transitioning from planar routing to three-dimensional routing through layered PCB construction, where connecting lines pass through different vertical levels to reach electrode elements without interfering with each other
3Ease of manufacture
If the number of layers is reduced to simplify production, then ease of manufacture is improved, but manufacturing precision must be maintained to ensure touch accuracy
Solution Approach 1:
The patent incorporates electrode elements and connecting lines directly into the PCB during the PCB manufacturing process itself, performing the electrode formation action beforehand as part of standard PCB fabrication rather than as a separate post-processing step
Solution Approach 2:
The patent merges the electrode array formation with the PCB manufacturing process, combining what were previously separate fabrication steps into a single integrated process that maintains precision while simplifying production
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
This design enhances touch resolution and accuracy, simplifies production, reduces costs, and maintains good optical properties by using a single layer with varying electrode densities, allowing for efficient and reliable touch detection without visible interference.
Implementation Method 1
capacitive sensors rely on the capacitance of a finger changing the capacitance detected by an array of elements overlaying the display device
Data Source
AI summary
An assembly has an array of first electrodes distributed across an active area of the touchscreen assembly such that the density of first electrodes increases in a first direction across the touchscreen. An array of second electrodes is distributed across an active area of the touchscreen assembly such that the density of second electrodes decreases in the first direction across the touchscreen.