Auxiliary Electrode Layer for OLED Voltage Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-resolution OLED displays face challenges due to increased wire resistance and voltage drops in larger displays, leading to uneven illumination and reduced luminous efficiency, which are exacerbated by the process of adding an auxiliary electrode layer that can damage the light emitting layer.
Innovation Solution
A display module with an auxiliary electrode layer integrated into the encapsulation layer, electrically connected to the cathode layer through a conductive connector, which supports uniform voltage distribution and prevents damage to the light emitting layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If an auxiliary electrode layer is added after the light emitting layer to prevent voltage drop, then cathode voltage uniformity is improved, but the light emitting layer is damaged due to high temperature processing
Solution Approach 1:
The auxiliary electrode layer is formed before the light emitting layer during the same vacuum deposition process, rather than adding it afterward. This preliminary action allows the auxiliary electrode to be in place during light emitting layer formation, preventing voltage drop without requiring subsequent high-temperature processing that would damage the organic materials.
Solution Approach 2:
The invention changes the processing temperature parameter by forming the auxiliary electrode at low temperature (below the decomposition temperature of organic materials) rather than high temperature. This is achieved by using vacuum deposition techniques that allow low-temperature fabrication, thus protecting the light emitting layer from thermal damage while still achieving voltage uniformity.
2Ease of operation
If the cathode is disposed in the entire layer of the OLED display, then common voltage provision is achieved, but wire resistance increases causing voltage drop
Solution Approach 1:
The cathode is segmented into multiple regions with different functions: a common cathode layer for voltage provision and a patterned auxiliary electrode layer for voltage compensation. The auxiliary electrode is divided into multiple segments corresponding to different pixel regions, allowing localized voltage adjustment to compensate for wire resistance effects while maintaining overall common voltage provision.
Solution Approach 2:
The auxiliary electrode layer acts as an intermediary between the common cathode and the light emitting layer. It mediates the voltage distribution by providing additional conductive pathways that compensate for resistance losses in the main cathode structure, thereby reducing voltage drop without changing the fundamental common cathode architecture.
3Manufacturing precision
If high resolution is pursued in larger displays, then display detail is improved, but wire resistance and voltage drop are exacerbated
Solution Approach 1:
The invention addresses the voltage drop problem by adding a dimensional layer (the auxiliary electrode layer) between the cathode and light emitting layer, rather than trying to optimize the cathode structure itself. This third dimension provides additional conductive pathways that compensate for resistance effects in high-resolution, large-area displays without compromising pixel density or resolution.
Data Source
AI summary
Provided are a display module and an electronic device. The display module includes an array substrate and an encapsulation layer disposed opposite to the array substrate, and the encapsulation layer includes an auxiliary electrode layer and a first electrical connector between the encapsulation layer and the array substrate; wherein the first electrical connector is used to support the encapsulation layer and is electrically connected to the auxiliary electrode layer and the cathode layer.