Multi-Layer Touch Sensor Structure for Narrow-Bezel Display Panels
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices face challenges in reducing bezel size while maintaining high touch sensitivity and minimizing noise between sensor electrodes.
Innovation Solution
A display device and panel design with a touch sensor structure that includes multiple sensor electrodes and routing lines in different metal layers, allowing for a narrow bezel and improved touch sensitivity, with internal touch routing lines that do not pass through the non-display area.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If the bezel size is reduced, then the display area ratio is improved, but the touch sensitivity and noise reduction between sensor electrodes deteriorate
Solution Approach 1:
The patent applies multi-layer stacking of sensor electrodes and routing lines in the vertical dimension (different metal layers) to achieve narrow bezel while maintaining touch sensitivity. By distributing components across multiple layers rather than expanding them horizontally, the bezel width is reduced without compromising the electrical performance of the touch sensor.
Solution Approach 2:
The sensor electrode is divided into multiple sub-sensor electrodes (first, second, third sensor electrodes) that are electrically connected through bridges. This segmentation allows the touch sensing function to be distributed across multiple elements, enabling narrower bezel design while maintaining the overall touch sensitivity through the combined effect of segmented electrodes.
2Area of stationary object
If the bezel size is reduced, then the display area ratio is improved, but the noise between sensor electrodes increases
Solution Approach 1:
Routing lines are assigned to different metal layers than sensor electrodes (e.g., sensor electrodes in first and second metal layers, routing lines in third metal layer). This vertical separation in the multi-layer structure prevents electromagnetic coupling and noise between routing lines and sensor electrodes, enabling narrow bezel design without increasing noise interference.
Solution Approach 2:
The patent introduces intermediate insulation layers and spatial separation through multi-layer stacking as mediators between routing lines and sensor electrodes. These intermediate structures act as barriers that prevent direct electromagnetic interaction, reducing noise while allowing the components to be positioned close together for narrow bezel.
3Reliability
If multiple sensor electrodes are added to improve touch sensitivity, then the touch sensitivity is improved, but the device complexity increases
Solution Approach 1:
Multiple sensor electrodes and routing lines are merged into a single integrated structure using the same metal layer deposition process. The first, second, and third sensor electrodes along with their corresponding routing lines are formed in sequence during the metal layer fabrication, combining multiple functions into one integrated component rather than separate assemblies.
Solution Approach 2:
The metal layers serve multiple functions: first and second metal layers contain both sensor electrodes and routing lines, while the third metal layer contains routing lines. This multi-functional use of metal layers reduces the overall structural complexity compared to having dedicated separate layers for each component, enabling enhanced touch sensitivity without proportional increase in device complexity.
Data Source
AI summary
A display device can include a display area and a non-display area; a plurality of first sensor electrodes disposed in the display area, a plurality of second sensor electrodes disposed in the display area, a plurality of first pads disposed in the non-display area, a plurality of second pads disposed in the non-display area, a plurality of first touch routing lines electrically connecting the plurality of first sensor electrodes with the plurality of first pads, and a plurality of second touch routing lines electrically connecting the plurality of second sensor electrodes with the plurality of second pads. Also, one of the plurality of first touch routing lines electrically connected to at least one of the plurality of first sensor electrodes overlaps with at least another one of the plurality of first sensor electrodes that is electrically connected to another first touch routing line.