Nanostructured Lamination for OLED Light Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for patterning nanostructures on large substrates for applications in display, lighting, and photovoltaic devices are costly and inefficient, particularly in forming nanostructured surfaces for enhanced light extraction in OLED devices.
Innovation Solution
The use of nanostructured light extraction color filter laminates, involving a high index optical coupling layer and a nanostructured transfer layer, is applied to OLED devices through lamination techniques to enhance light extraction efficiency, particularly in color-by-white OLED displays, by forming a nanostructured surface in optical contact with the emitting surface of the OLED.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If traditional photolithographic methods are used to pattern nanostructures on large substrates, then manufacturing precision can be achieved, but the process becomes costly and inefficient with multiple solvent-based steps
Solution Approach 1:
The patent uses a master template with pre-formed nanostructures that is replicated onto the OLED substrate through lamination. This copying approach transfers the nanostructure pattern without requiring traditional photolithographic steps, thereby maintaining manufacturing precision while dramatically simplifying the fabrication process and eliminating solvent-based steps
Solution Approach 2:
The patent replaces the chemical-based photolithographic system with a mechanical lamination system. The master template is physically pressed onto the OLED substrate to transfer nanostructures, substituting complex chemical processes with a simpler mechanical transfer process that achieves the same patterning result
2Loss of energy
If nanostructures are formed on OLED surfaces to enhance light extraction, then light extraction efficiency is improved, but the device complexity and fabrication difficulty increase
Solution Approach 1:
The nanostructures are pre-formed on a separate master template before being transferred to the OLED substrate. This preliminary action allows the complex nanostructure fabrication to be performed once on the template, rather than directly on the OLED, thereby improving light extraction efficiency while minimizing the complexity added to the OLED fabrication process
Solution Approach 2:
The patent separates the nanostructure fabrication function from the OLED fabrication process by using a distinct master template. This segmentation allows the OLED to be manufactured using standard processes while the light extraction enhancement is added through a separate lamination step, reducing overall device complexity
3Device complexity
If conventional light extraction methods are used in CBW OLED displays, then the structure remains simple, but light outcoupling efficiency is insufficient
Solution Approach 1:
The patent applies nanostructures only at specific locations where light extraction is needed, rather than modifying the entire OLED structure. The master template contains nanostructures that are transferred to contact with the emitting surface, providing localized enhancement of light outcoupling efficiency while maintaining overall structural simplicity
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 approach results in improved light outcoupling and a thin, easy-to-fabricate design for OLEDs, eliminating the need for solvent-based photolithographic steps and enabling nanopatterning without traditional solvent usage, thus enhancing light extraction efficiency and simplifying the fabrication process.
Implementation Method 1
The index of refraction of the nanostructured template layer is lower than the index of refraction of the high index nanostructured transfer layer
Implementation Method 2
nanostructures for light extraction or light distribution
Data Source
Figure 1A
Figure 1B
Figure 1C
AI summary
The present disclosure describes nanostructured light extraction color filter laminates, and articles and methods of using nanostructured light extraction color filter laminates for the fabrication of an OLED including a nanostructure, using lamination techniques. Nanostructured OLED devices can exhibit enhanced light extraction efficiency. The methods involve transfer and/or replication of a film, layer, or coating in order to form a nanostructured surface that is in optical contact with the emitting surface of an OLED in, for example, a top emitting or a bottom emitting active matrix OLED (TE-AMOLED or BE-AMOLED) device. The articles having enhanced light extraction efficiency can be of particular use in color-by-white (CBW) OLED displays, which use white-light spectrum OLEDs with a color filter array.