Flexible Display Stack-Up With Liquid Interface For Foldable Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in creating foldable electronic devices is the limited flexibility due to stiffness and stress to failure, which complicates the integration of display layers with additional components like touch panels and protective layers.
Innovation Solution
A flexible display stack-up is designed with multiple layers, including a display layer, touch panel, and lens, where a non-adhesive liquid is used between layers, and an outer seal made of flexible material is positioned along the lateral surface to allow relative sliding, reducing stiffness and stress, enabling greater flexibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple layers (display, touch panel, protective layers) are integrated to create a foldable device, then the device functionality is improved, but the stiffness and stress to failure increase, limiting flexibility
Solution Approach 1:
The patent divides the rigid adhesive bonding system into segments by introducing a liquid layer between the display layer and touch panel layer. This segmentation allows independent movement of each layer while maintaining overall structural integrity, enabling the stacked assembly to bend without excessive stress accumulation.
Solution Approach 2:
The patent introduces a liquid intermediary substance between the display layer and touch panel layer. This liquid acts as a mediator that transmits minimal stress between layers while allowing relative sliding, thereby reducing the overall stress to failure of the multi-layer structure and enabling foldability.
2Stability of the object's composition
If layers are rigidly bonded together, then structural stability is improved, but flexibility and ability to bend are reduced
Solution Approach 1:
The patent transitions from a static rigid adhesive bond to a dynamic liquid interface that can adapt its properties during bending. The liquid layer allows the structure to dynamically adjust during flexing operations, maintaining stability in the unbent state while enabling flexibility during bending through controlled layer sliding.
Solution Approach 2:
The patent employs a thin liquid film between layers to create a flexible interface. This thin film structure maintains structural stability when flat but allows the assembly to bend flexibly when curved, effectively decoupling the stability and flexibility requirements of the multi-layer structure.
3Ease of manufacture
If adhesive bonding is used between layers, then layer integration is improved, but stress concentration and risk of breaking increase during bending
Solution Approach 1:
The patent replaces the mechanical adhesive bonding system with a liquid-based interface system. This substitution eliminates the stress-concentrating adhesive layers while maintaining layer integration through the liquid medium, significantly improving stress resistance during bending operations.
Solution Approach 2:
The patent changes the physical state parameter of the bonding medium from solid (adhesive) to liquid. This parameter change fundamentally alters the stress transmission characteristics between layers, allowing the structure to withstand bending stresses that would cause adhesive-bonded structures to fail.
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 configuration reduces stiffness by a factor of four and stress by a factor of two, allowing the display stack-up to bend without breaking, supporting concave and convex bending, and enabling a more robust and flexible electronic device structure.
Implementation Method 1
The outer seal also contains a non-adhesive liquid between the second layer and the at least one other layer of the multiple layers to allow relative sliding between at least two layers of the multiple layers. This relative sliding reduces the stiffness and stress to failure within a display stack-up having multiple layers
Data Source
AI summary
A display stack-up for an electronic device has: multiple layers that include a display layer and a second layer; and an outer seal. Each layer has first and second base surfaces and a thickness therebetween defining a height of a lateral surface at a periphery of the layer. The multiple layers are stacked along an axis perpendicular to their base surfaces and parallel to their lateral surfaces, and the outer seal is positioned along the lateral surface of at least some of the multiple layers. The outer seal is composed of a flexible material and is arranged to bind the second layer and at least one other layer of the multiple layers. The outer seal also contains a non-adhesive liquid between the second layer and the at least one other layer to allow relative sliding between at least two layers of the multiple layers.