Quantum Dot OLED Scattering Layers to Reduce Blue Light Leakage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing quantum dot organic light-emitting diodes face limitations in increasing quantum dot concentration due to dot-to-dot energy transfer efficiency and stability issues, leading to decreased reemission efficiency and blue light leakage.
Innovation Solution
A quantum dot organic light-emitting diode structure is designed with a blue OLED layer, quantum dot color conversion layers having different scattering particle structures for R, G, and B colors, color filter layers to filter unwanted light, and a coating layer to enhance color conversion efficiency and reduce blue light leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If quantum dot concentration is increased to improve color conversion efficiency, then more blue light is absorbed and reemitted, but dot-to-dot energy transfer decreases efficiency and causes condensation leading to degradation of light-emitting property
Solution Approach 1:
The patent introduces scattering particles with specific size ranges (0.1-10 μm) and refractive indices (1.3-1.6) to create localized optical path modifications within the quantum dot layer. This allows different regions of the layer to have optimized light interaction properties, enabling high quantum dot concentration without uniform condensation issues throughout the entire layer.
Solution Approach 2:
Scattering particles serve as intermediary elements between the blue light source and quantum dots. These particles first scatter the incident blue light to increase path length and absorption probability, then allow quantum dots to convert the scattered light. This intermediary role reduces direct quantum dot-to-quantum dot energy transfer while maintaining overall conversion efficiency.
2Productivity
If thickness of quantum dot color conversion layer is increased to improve blue light absorption, then more quantum dots are available for conversion, but scattering particle stability decreases and particles precipitate
Solution Approach 1:
The patent optimizes scattering particle parameters including size (0.1-10 μm), concentration (0.1-10 wt%), and refractive index (1.3-1.6) to achieve the desired balance. By carefully controlling these parameters, the layer thickness can be increased for better absorption while maintaining particle suspension stability through optimized surface properties and concentration levels.
3Productivity
If scattering particles are inserted to improve blue light scattering and increase optical path, then color conversion efficiency improves, but it is difficult to insert certain concentration of scattering particles and they precipitate
Solution Approach 1:
The patent specifies optimal scattering particle concentration ranges (0.1-10 wt%) and size distributions (0.1-10 μm) that balance scattering effectiveness with manufacturability. These parameter optimizations ensure sufficient scattering particles are present to extend optical paths while remaining below precipitation thresholds and compatible with standard coating processes.
Solution Approach 2:
The patent creates a composite structure combining quantum dots, scattering particles, and binder materials in specific ratios. This composite approach allows scattering particles to be uniformly distributed within the matrix, improving ease of manufacture through single-step coating processes while maintaining the scattering functionality needed for extended optical paths.
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 structure achieves high color conversion efficiency and reduces blue light leakage by utilizing a low concentration of scattering particles with mixed shapes, improving optical path and absorption rates.
Implementation Method 1
a quantum dot color conversion layer which is provided on the blue OLED layer and has different scattering particle structures according to R, G and B colors
Implementation Method 2
uses the principle that a color conversion layer composed of red and green quantum dots absorbs the light of blue OLED and re-emits as much light as the band gap energy of the quantum dots themselves
Implementation Method 3
a quantum dot color conversion layer which is provided on the blue OLED layer and has different scattering particle structures according to R, G and B colors
Implementation Method 4
a color filter layer which is provided on the quantum dot color conversion layer and filters color other than the color that the color filter layer passes from the colors emitted by the quantum dot color conversion layer
Data Source
AI summary
A quantum dot organic light-emitting diode according to an embodiment of the present disclosure may include a blue organic light-emitting diode (OLED) layer, a quantum dot color conversion layer which is provided on the blue OLED layer and has different scattering particle structures according to R, G and B colors, a color filter layer which is provided on the quantum dot color conversion layer and filters color other than the color that the color filter layer passes from the colors emitted by the quantum dot color conversion layer, and a coating layer provided on the color filter layer.