Conductive Reflector for OLED Light Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic EL displays face challenges in improving light extraction efficiency and luminance due to limitations in signal transmission to light-emitting elements, particularly with high-resistance second electrodes affecting display performance and light extraction efficiency.
Innovation Solution
A display unit with a reflector having a conductive layer electrically coupled to the second electrode of the light-emitting element, which enhances signal flow and luminance by acting as both a reflector and auxiliary wiring, eliminating the need for additional wiring patterns and simplifying manufacturing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a reflector structure is provided at the periphery of the light-emitting section, then light extraction efficiency is improved, but device complexity increases due to additional structural components
Solution Approach 1:
The reflector and wiring pattern are merged into a single integrated structure. The conductive layer serves dual functions: reflecting light to improve extraction efficiency and conducting electrical signals to the light-emitting elements. This eliminates the need for separate reflector structures and additional wiring patterns, thereby reducing device complexity while maintaining improved light extraction efficiency.
Solution Approach 2:
The conductive layer of the reflector is designed to perform multiple functions simultaneously: it acts as both a light-reflecting surface and an electrical wiring pattern. This multi-functional design allows the same structural element to contribute to both optical performance (light extraction) and electrical function (signal transmission), simplifying the overall device architecture.
2Illumination intensity
If signal amount to light-emitting elements is increased, then luminance is improved, but manufacturing complexity increases due to additional wiring requirements
Solution Approach 1:
The wiring pattern required for signal transmission is merged with the reflector structure. The conductive layer that forms the reflector also serves as the wiring pattern, eliminating the need for separate wiring layers or additional patterning steps. This integration simplifies manufacturing processes while enabling increased signal amounts to improve luminance.
Solution Approach 2:
The conductive layer is designed with multi-functionality, serving both as a reflector for light extraction enhancement and as a wiring pattern for signal transmission. This dual-purpose design reduces the number of manufacturing steps required, as the same layer is formed and patterned to fulfill both optical and electrical requirements, thereby easing manufacturing complexity.
3Illumination intensity
If additional wiring patterns are added to increase signal flow, then luminance is improved, but device complexity and manufacturing cost increase
Solution Approach 1:
The wiring patterns needed for increased signal flow are merged into the reflector structure. The conductive layer is configured to provide both the reflector geometry and the wiring connections, eliminating the need for additional wiring layers or patterns. This integration maintains improved luminance performance while reducing device complexity and manufacturing cost.
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 improves light extraction efficiency, increases luminance, and maintains high aperture rates, enabling more efficient light emission and cost-effective manufacturing while ensuring uniform light distribution across the display region.
Implementation Method 1
a reflector that is provided at a periphery of the light-emitting section to reflect light from the light-emitting section
Implementation Method 2
the conductive layer being electrically coupled to the second electrode of the light-emitting element
Implementation Method 3
An organic EL (Electroluminescence) display with use of self-emitting type light-emitting elements
Data Source
AI summary
A display unit includes: a light-emitting section including a light-emitting element that has a first electrode, an organic layer including a light-emitting layer, and a second electrode in this order; and a reflector that is provided at a periphery of the light-emitting section to reflect light from the light-emitting section, and has a conductive layer, the conductive layer being electrically coupled to the second electrode of the light-emitting element.