Touch Signal Line Routing in Display Devices
Solution Overview
Problem
Display devices with touch panels face issues of coupling and short failures between touch lines and test lines, which affect the reliability and performance of touch input recognition.
Innovation Solution
The implementation of a display device design where touch signal lines and touch test lines are separated and connected through distinct conductive layers, with touch connection lines using a different conductive layer than the signal lines and test lines, preventing direct intersection and potential coupling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If touch signal lines and touch test lines are disposed in the same conductive layer, then the manufacturing process is simplified, but coupling and short failures occur between the lines
Solution Approach 1:
The patent applies dimensionality change by transitioning from a two-dimensional planar arrangement to a three-dimensional layered structure. Touch signal lines and touch test lines are separated into different conductive layers (first and second conductive layers), with connection lines extending in the thickness direction to connect corresponding terminals. This vertical separation eliminates coupling and short failures while maintaining manufacturing feasibility through standardized multi-layer conductor formation processes.
2Reliability
If touch connection lines intersect touch signal lines, then electrical connection is achieved, but coupling failures may occur
Solution Approach 1:
The connection lines are configured to extend primarily in the thickness direction rather than horizontally intersecting signal lines. By utilizing the vertical dimension for connection path routing, the design achieves reliable electrical connection between touch signal lines and test lines while minimizing horizontal overlap and coupling risk.
Solution Approach 2:
The patent introduces an insulating layer as an intermediary between the first conductive layer containing touch signal lines and the second conductive layer containing touch test lines. This insulating barrier prevents direct electrical coupling between adjacent lines in different layers, allowing safe intersection in plan view while maintaining electrical isolation, with connections established only where intended through controlled conductor patterns.
Data Source
AI summary
A display device includes a first area including a display area, a second area including a pad area, a bending area disposed between the first area and the second area, a plurality of touch signal lines extending from the second area to the first area through the bending area, a plurality of touch test lines disposed in the second area and separated and spaced apart from the plurality of touch signal lines, and a plurality of touch connection lines electrically connecting the plurality of touch signal lines and the plurality of touch test lines, wherein, in the second area, the plurality of touch signal lines and the plurality of touch test lines include a first conductive layer, and the plurality of touch connection lines includes a second conductive layer different from the first conductive layer.