Selective Transmission Layer for OLED Light Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current self-light emitting display devices face challenges in enhancing light extraction efficiency and color conversion efficiency, with existing technologies often requiring high-temperature plasticity that can lead to material deterioration and inefficiencies.
Innovation Solution
A self-light emitting display device design featuring a blue light emitting diode, color conversion patterns, and a selective transmission layer that transmits blue light and reflects red and green light, minimizing recycled light loss and eliminating the need for high-temperature processes, thereby improving light extraction and color conversion efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a conventional OLED structure with multiple organic layers is used, then light emission is achieved, but light extraction efficiency is limited due to total internal reflection at the interface
Solution Approach 1:
A selective transmission layer is introduced as an intermediary component between the OLED structure and the external environment. This layer selectively transmits blue light while reflecting red and green light back into the OLED, enabling light recycling without requiring high-temperature plasticity processes that cause material deterioration
Solution Approach 2:
The selective transmission layer utilizes wavelength-dependent optical properties to differentiate between blue light (which is transmitted) and red/green light (which is reflected). This color-selective behavior enables efficient light extraction for blue wavelengths while recycling longer wavelengths back into the emitting layer, improving overall light extraction efficiency without material degradation
2Illumination intensity
If high-temperature plasticity processes are applied to improve light extraction, then light extraction efficiency increases, but material deterioration occurs and lifespan decreases
Solution Approach 1:
The patent replaces mechanical/thermal processing methods (high-temperature plasticity) with an optical solution (selective transmission layer). This substitution achieves light extraction enhancement through optical wavelength selection rather than thermal-mechanical deformation, thereby avoiding material deterioration and extending device lifespan while maintaining improved light extraction efficiency
3Illumination intensity
If color conversion patterns are added to convert blue light to red and green light, then color conversion efficiency is improved, but manufacturing complexity increases
Solution Approach 1:
The selective transmission layer is integrated directly into the OLED stack structure, merging the light management function with the existing device architecture. This integration approach combines color conversion and light extraction functions in a unified structure, improving color conversion efficiency while avoiding the need for separate, complex manufacturing processes
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 proposed design enhances light extraction efficiency and extends the lifespan of the display device by reducing material deterioration and optimizing color conversion, while also simplifying the manufacturing process and reducing misalignment errors between substrates.
Implementation Method 1
The selective transmission layer reflects the green light and the red light
Implementation Method 2
The selective transmission layer transmits blue light and reflects red light and green light
Implementation Method 3
The red color converting unit is disposed between the partitions in the first region to convert the blue light into red light
Implementation Method 4
The green color converting unit is disposed between the partitions in the second region to convert the blue light into green light
Implementation Method 5
a blue light emitting diode disposed in at least one pixel and emits blue light
Data Source
AI summary
A self-light emitting display device comprises at least one pixel comprising a first region, a second region and a third region; a blue light emitting diode disposed in the at least one pixel and configured to emit blue light; partitions disposed over the blue light emitting diode and spaced apart from one another, the partitions defining the first region, the second region and the third region; a color conversion pattern disposed over the blue light emitting diode and including a red color converting unit disposed between the partitions in the first region and configured to convert the blue light into red light and a green color converting unit disposed between the partitions in the second region and configured to convert the blue light into green light; and a selective transmission layer configured to transmit the blue light and to reflect the green light and the red light and comprising a first selective transmission region corresponding to the first and second regions, wherein the first selective transmission region includes a first bottom portion disposed between the color conversion pattern and the blue light emitting diode, and a first wall portion disposed between the color conversion pattern and partitions and extending from the first bottom portion.