Organic Light Emitting Display Device with PWES Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic light emitting display devices experience color defects and differences due to variations in peak wavelength when viewed from different positions or angles, making it difficult to achieve a uniform color display.
Innovation Solution
The design optimizes the moving range of the peak wavelength of the electroluminescence (EL) spectrum by setting a peak wavelength of EL spectrum (PWES) structure, ensuring the peak wavelength remains within a specific range (e.g., ±10 nm) across various positions and angles, using a configuration with emission layers and charge generation layers to maintain consistent color coordinates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a multilayer emission method with different peak wavelengths is used to emit white light, then the emission efficiency and luminance are improved, but the peak wavelength changes depending on viewing position and angle, causing color defects and non-uniform display
Solution Approach 1:
The patent optimizes the thickness parameters of organic emission layers to control the electroluminescence spectrum. By adjusting layer thicknesses, the peak wavelength shift with viewing angle is minimized, keeping the spectrum within a controlled moving range and reducing color defects while maintaining emission efficiency
Solution Approach 2:
The patent acknowledges and manages the dynamic nature of the electroluminescence spectrum that changes with viewing angle. Instead of attempting to completely eliminate the shift, the invention controls the spectrum's moving range through layered structure optimization, accepting controlled variation while preventing excessive color deviation
2Illumination intensity
If multiple emission layers with different peak wavelengths are combined to achieve white light emission, then the luminance and emission efficiency are enhanced, but the color coordinates become unstable when viewed from different positions
Solution Approach 1:
The patent precisely controls the thickness parameters of each organic emission layer to optimize the combined electroluminescence spectrum. This parameter optimization ensures that the peak wavelength remains stable across different viewing positions while maintaining high luminance output from the multilayer structure
Solution Approach 2:
The patent uses a composite multilayer organic emission structure where different layers with distinct peak wavelengths are combined. By optimizing the composition and thickness of each layer, the composite structure achieves stable color coordinates and high luminance simultaneously, resolving the contradiction between emission performance and 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
This solution effectively reduces color defects and differences, ensuring a uniform color display across different viewing positions and angles by stabilizing the peak wavelength of the EL spectrum, thereby enhancing the display's color consistency and accuracy.
Implementation Method 1
An electron and a positive hole are injected from the two electrodes into the organic emission layer, and an exciton is generated by combining the electron with the positive hole. The organic light emitting device is a device using the principle that light is emitted when the generated exciton is dropped from an excited state to a ground state.
Data Source
AI summary
An organic light emitting display device includes a first electrode and a second electrode on a substrate, the first electrode being opposite to the second electrode; and at least one emission part between the first electrode and the second electrode, the at least one emission part including at least one organic layer, wherein the at least one organic layer comprises a peak wavelength of electroluminescence (EL) spectrum (PWES) structure where a moving range of a peak wavelength of an EL spectrum emitted from the at least one emission part is set.