OLED Display Light Shielding Member for Luminance Degradation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic light emitting diode (OLED) displays face issues with luminance and life reduction due to oxidation of the organic light emitting layer by moisture and fluorine generated from organic materials in the planarization layer and pixel defining layer, leading to color deviation and non-light emitting areas over time.
Innovation Solution
The OLED display incorporates a pixel defining layer that partially exposes a first electrode, an organic light emitting layer with a main area and a sub area overlapping the pixel defining layer, and a thin-film encapsulation layer with a light shielding member. The organic light emitting layer includes a shadow portion and a sub area that change to non-light emitting areas as time elapses, with the light shielding member overlapping the pixel defining layer to block mixed light emission, and a charge generation layer between light emitting layers to improve luminous efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the organic light emitting layer is exposed to moisture and fluorine from organic materials in the planarization layer and pixel defining layer, then the organic light emitting layer generates light initially, but over time oxidation occurs leading to luminance reduction, life reduction, color deviation, and formation of non-light emitting areas
Solution Approach 1:
The patent applies thin-film encapsulation layers (inorganic and organic) to protect the organic light emitting layer from moisture and fluorine. Multiple thin film layers are stacked to provide effective barrier protection, preventing oxidation and extending device life while maintaining luminance over time.
Solution Approach 2:
The patent creates a protective environment by using inorganic encapsulation layers that act as barriers against moisture and fluorine-containing gases. This effectively isolates the organic light emitting layer from harmful atmospheric components, preventing oxidation reactions.
2Manufacturing precision
If the pixel defining layer and organic materials are used to structure the display, then the display achieves proper pixel definition and structure, but fluorine is generated from these organic materials leading to oxidation of the organic light emitting layer
Solution Approach 1:
The patent extracts and removes fluorine-containing organic materials from the pixel defining layer and planarization layer formulations. By selecting materials that do not contain fluorine, the harmful fluorine generation is eliminated while maintaining the structural and definitional functions of these layers.
Solution Approach 2:
The patent converts the potential harm of using organic materials in pixel defining layers by carefully selecting materials that avoid fluorine content. This transforms the material selection process into a benefit by preventing oxidation while maintaining the necessary structural functions.
3Illumination intensity
If the organic light emitting layer is fully exposed in the main area, then strong light emission is achieved, but the shadow portion and sub area emit mixed light and degrade over time reducing overall display quality
Solution Approach 1:
The patent applies different characteristics to different areas of the organic light emitting layer. The main area is designed for strong light emission, while the shadow portion and sub area are managed to prevent mixed light emission. The light shielding member is selectively positioned to block light from specific areas, ensuring color accuracy is maintained where needed.
Solution Approach 2:
The patent introduces a light shielding member as an intermediary element between the organic light emitting layer and the viewer. This member selectively blocks light from the shadow portion and sub area, preventing mixed light from reaching the display output and thereby maintaining color accuracy without affecting the main emission area.
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 helps maintain the light emitting area, reduces luminance and life degradation, and minimizes color deviation by effectively encapsulating the organic light emitting layer and managing light emission, thereby enhancing the display's reliability and optical characteristics.
Implementation Method 1
a light shielding member on the thin-film encapsulation layer overlapping the pixel defining layer
Implementation Method 2
a thin-film encapsulation layer on the organic light emitting layer
Data Source
AI summary
An organic light emitting diode (OLED) display includes a first electrode, a pixel defining layer that at least partially exposes the first electrode, an organic light emitting layer on the first electrode, a thin-film encapsulation layer on the organic light emitting layer, and a light shielding member on the thin-film encapsulation the light shielding member overlapping the pixel defining layer. The organic light emitting layer includes a main area not overlapping the pixel defining layer and a sub area overlapping the pixel defining layer. The main area includes an open portion not overlapping the light shielding member and a shadow portion around the open portion overlapping the light shielding member.