Multi-layer Encapsulation for Flexible Display Color Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Flexible display devices face challenges in maintaining color consistency and protecting light-emitting elements due to transmittance variations caused by ambient light, which can lead to damage from increased light exposure.
Innovation Solution
A display device design featuring a thin film encapsulation layer with a multi-layer structure of alternating refractive indices, integrated touch sensing electrodes, and an insulating layer to manage light transmittance and prevent UV damage, ensuring flexibility and reduced color variation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the light transmittance through the thin film encapsulation layer is increased to reduce color variation, then the color consistency is improved, but the light emitting elements may be damaged due to increased light exposure
Solution Approach 1:
The encapsulation layer is divided into multiple sub-layers with alternating high and low refractive indices. This segmentation allows the structure to selectively transmit visible light while reflecting harmful UV light, resolving the contradiction between color consistency and light damage protection
Solution Approach 2:
The patent uses composite material structure combining materials with different refractive indices (e.g., SiO2 with n=1.46 and TiO2 with n=2.6) to create an optical interference structure that achieves both high visible light transmittance and UV light reflection, simultaneously improving color consistency and protecting light emitting elements
2Stability of the object's composition
If a multi-layer structure with alternating refractive indices is used to control light transmittance, then color variation is reduced and UV protection is improved, but the device complexity increases
Solution Approach 1:
The encapsulation layer is segmented into multiple thin sub-layers (typically 3-7 layers) with alternating refractive indices. This segmentation creates optical interference effects that control light transmission without requiring thick individual layers, maintaining color consistency while managing structural complexity through systematic layering
Solution Approach 2:
The patent optimizes specific parameters including layer thickness (typically 50-200 nm per layer), refractive index contrast (difference > 0.5), and number of layers to achieve maximum UV reflection while maintaining visible light transmittance. These parameter optimizations balance the benefits of multi-layer structure against the increased device complexity
3Adaptability or versatility
If the thin film encapsulation layer is made thinner to maintain flexibility, then the flexibility is improved, but the color variation and light damage risk increase
Solution Approach 1:
Instead of using a single thick encapsulation layer, the patent segments the encapsulation into multiple thin sub-layers. This segmentation maintains overall thinness and flexibility while the collective optical interference effect of multiple layers provides superior color consistency and UV protection compared to a single thin layer
Solution Approach 2:
The patent employs composite material structure with alternating high and low refractive index materials in thin layers. This composite approach achieves enhanced optical performance (reduced color variation and UV protection) at the same or reduced total thickness, thereby maintaining flexibility while improving color consistency
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
The solution effectively reduces color changes and protects light-emitting elements by controlling light transmittance and UV exposure, maintaining display quality while maintaining the flexibility of the display panel.
Implementation Method 1
at least one of the thin film encapsulation layer and the insulating layer has a multi-layer structure including first and second alternating layers forming at least three layers, and the first layer includes a first material having a first refractive index and the second layer includes a second material having a second refractive index different from the first refractive index
Implementation Method 2
the first layer includes a first material having a first refractive index and the second layer includes a second material having a second refractive index different from the first refractive index
Data Source
AI summary
A display device includes a light-emitting element, a thin film encapsulation layer disposed on the light-emitting element, a protection layer disposed on the thin film encapsulation layer, a first sensing electrode disposed on the protection layer, an insulating layer disposed on the first sensing electrode, and a second sensing electrode disposed on the insulating layer, in which at least one of the thin film encapsulation layer and the insulating layer has a multi-layer structure including first and second alternating layers forming at least three layers, and the first layer includes a first material having a first refractive index and the second layer includes a second material having a second refractive index different from the first refractive index.