Flexible Display Bent Inactive Region for Neutral-Plane Signal Lines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Flexible display devices face challenges in maintaining performance and reliability when bent at small radii due to increased stress, which can lead to signal line resistivity and reliability issues.
Innovation Solution
The use of a flexible substrate with a signal line disposed between inorganic layers, where the signal line is electrically connected to an electrode or thin film transistor, and the substrate is configured to maintain a neutral plane that reduces stress on the signal line during bending, allowing for efficient and reliable deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If the bend radius of the outlying area is decreased to reduce planar surface area, then the aesthetic appeal and ergonomic design are improved, but the stress on the bending area increases which may increase resistivity and reduce reliability of signal lines
Solution Approach 1:
The patent applies different structural configurations to different regions of the flexible substrate. Specifically, the signal line is positioned within a neutral plane region that experiences minimal stress during bending, while other regions of the substrate can be freely deformed. This local differentiation allows the device to achieve small bend radii without compromising signal line reliability.
Solution Approach 2:
The patent transitions from a two-dimensional planar arrangement to a three-dimensional folded configuration. By folding the flexible substrate along predetermined lines, the outlying areas are brought closer to the display area in the third dimension (depth), effectively reducing the planar surface area while maintaining signal line integrity through strategic positioning within the folded structure.
2Volume of moving object
If the bend radius is decreased to enable more compact device configuration, then the device size is reduced, but the stress on signal lines increases causing increased resistivity
Solution Approach 1:
The patent creates a localized neutral plane within the flexible substrate where signal lines are positioned. This neutral plane region is specifically engineered to experience minimal mechanical stress during bending operations, allowing the rest of the device to be compactly folded while protecting the signal lines from harmful stress that would otherwise increase resistivity.
Solution Approach 2:
The neutral plane acts as an intermediary structure between the folded regions and the signal lines. By positioning signal lines within this neutral plane, the patent creates a protective buffer zone that mediates the mechanical stress, allowing compact device configuration without directly transmitting bending stress to the signal lines.
Data Source
AI summary
An apparatus including a flexible substrate, an electrode, and a signal line. The flexible substrate includes a first area extending along a plane, and a second area extending from the first area. The second area is bent away from the plane. The electrode overlaps the first area. The signal line is disposed in association with the first area and the second area. The signal line is electrically connected to the electrode. A neutral plane of the second area extends in the signal line.