OLED Mask Chamfered Corners for High-Resolution Color Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-resolution organic light emitting diode (OLED) displays face challenges in maintaining pixel integrity and preventing color mixing due to small pixel sizes and reduced distance between adjacent pixels, leading to manufacturing yield issues.
Innovation Solution
The OLED display incorporates polygonal openings in the pixel defining layer with chamfers or convex portions at the corners of the openings, and uses mask units with corresponding chamfers or convex portions to ensure precise deposition of organic emission layers, preventing overlap and color mixing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the pixel size is reduced to achieve high resolution, then the display resolution is improved, but the distance between adjacent pixels decreases causing color mixing
Solution Approach 1:
The pixel structure is segmented into distinct functional zones: a central emission region and corner regions with chamfers. This segmentation allows the emission layer to be confined to specific areas, preventing it from spreading into adjacent pixels while maintaining high resolution through the overall pixel arrangement.
Solution Approach 2:
Different regions of the pixel have different structural characteristics. The corner regions feature chamfers (cut corners) that create local geometric variations, while the central region maintains a standard polygonal shape. This local quality differentiation prevents emission layer intrusion at corners where pixels are closest, thereby preventing color mixing while preserving high resolution.
2Measurement precision
If the pixel size is reduced to achieve high resolution, then the display resolution is improved, but the manufacturing yield deteriorates
Solution Approach 1:
The chamfers are pre-formed on the mask structure before the organic emission layer deposition process. This preliminary action ensures that when the emission layer is deposited, it naturally follows the chamfered geometry and is confined to the intended pixel areas, preventing defects that would reduce manufacturing yield in high-resolution displays.
Solution Approach 2:
The chamfered mask structure acts as an intermediary between the deposition process and the final pixel pattern. It guides the organic emission layer material to deposit only in the desired regions, ensuring precise pattern formation even at high resolutions where direct patterning would be difficult and yield-reducing.
3Measurement precision
If the distance between adjacent pixels is reduced, then the display resolution is improved, but the organic emission layer intrudes into other openings causing color mixing
Solution Approach 1:
The pixel openings and mask patterns incorporate asymmetric chamfered corners instead of symmetric rectangular or circular shapes. This asymmetry creates directional guidance for the organic emission layer deposition, ensuring that the material flows and adheres to the intended pixel boundaries even when pixel spacing is minimal, thereby maintaining manufacturing precision at high resolutions.
Data Source
AI summary
An organic light emitting diode display including a first electrode, a pixel defining layer positioned on the first electrode and including a first opening having a first polygonal shape opening the first electrode, and a first organic emission layer positioned on the pixel defining layer through the first electrode corresponding to the first opening and including a first chamfer adjacent to a corner of the first opening.