Transparent OLED Second Electrode Oxide Layer Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Transparent display devices, particularly OLEDs, face challenges in achieving high light transmittance without compromising luminance, as increasing the transmissive area reduces the emissive area, leading to lower luminance when the device is on.
Innovation Solution
A transparent OLED display device is designed with a pixel defining layer that separates emissive and transmissive areas, featuring a first electrode, an organic light emitting layer, and a second electrode with an oxide layer in the transmissive area, along with a manufacturing method that includes using a mask with a blocking and transmissive portion to optimize the second electrode's oxidation, enhancing light transmittance without decreasing luminance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the transmissive area is increased to improve light transmittance, then the light transmittance is improved, but the emissive area is reduced leading to lower luminance
Solution Approach 1:
The patent applies local quality by differentiating the properties of different areas within the display device. The transmissive area and emissive area are given different characteristics: the transmissive area uses a transparent electrode with optimized oxidation to maximize light transmission, while the emissive area maintains standard electrode properties for optimal light emission. This localized differentiation allows each area to perform its function at peak efficiency without compromising the other.
Solution Approach 2:
The patent employs parameter changes by modifying the oxidation state of the transparent electrode in the transmissive area. By controlling the oxidation process through specific masks and conditions, the electrode's optical properties are adjusted to enhance light transmittance in the transmissive region while preserving the necessary electrical and emission properties in the emissive region. This parameter optimization resolves the contradiction between transmittance and luminance.
2Illumination intensity
If the transmissive area is increased to improve transparency, then the transparency is improved, but the display area is reduced
Solution Approach 1:
The patent applies local quality by differentiating the properties of different areas within the display device. The transmissive area and emissive area are given different characteristics: the transmissive area uses a transparent electrode with optimized oxidation to maximize light transmission, while the emissive area maintains standard electrode properties for optimal light emission. This localized differentiation allows each area to perform its function at peak efficiency without compromising the other.
3Illumination intensity
If the oxide layer is added to the second electrode in the transmissive area, then the light transmittance is improved, but the manufacturing complexity increases
Solution Approach 1:
The patent applies preliminary action by performing the oxidation of the transparent electrode during the manufacturing process itself, rather than as a separate post-processing step. The oxidation is conducted in-situ using controlled atmospheric processing with specific masks already in place, which prepares the electrode with the desired optical properties before final device assembly. This preliminary oxidation integrates the complexity into the existing manufacturing flow rather than adding separate steps.
Solution Approach 2:
The patent uses masks as intermediary tools to control the oxidation process. The masks selectively expose only the transmissive area to the oxidizing atmosphere, preventing oxidation in the emissive area. This intermediary approach allows precise spatial control of the oxidation reaction, achieving the desired differential electrode properties without requiring complex multi-step processing or additional equipment beyond standard manufacturing capabilities.
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 solution significantly improves light transmittance in the transmissive area while maintaining or reducing the decrease in luminance, allowing for a more transparent and effective display when the device is on.
Implementation Method 1
The second electrode includes an oxide layer in the transmissive area
Data Source
AI summary
A display device including a first substrate and a pixel defining layer disposed on the first substrate. The pixel defining layer is configured to define an emissive area and a transmissive area. The display device also includes a first electrode disposed in the emissive area, a light emitting layer disposed on the first electrode, and a second electrode disposed in the emissive area and the transmissive area. The second electrode includes an oxide layer in the transmissive area.