Non-Rectangular OLED Panel via Segmented Mask Stack
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing Fine Metal Mask (FMM) fabrication process struggles with creating organic light-emitting layers in non-rectangular shaped display areas, leading to poor planarity and precision issues, which complicates the design and evaporation processes, making it difficult to produce high-quality non-rectangular shaped display panels.
Innovation Solution
The use of a fine metal mask with rectangular evaporation areas and a shielding mask with non-rectangular shaped openings, arranged in a stack, allows for the creation of organic light-emitting layers in non-rectangular shaped pixel areas, improving the precision and design of the evaporation process, and enabling the production of seamless non-rectangular display panels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If a non-rectangular shaped fine metal mask is designed to match the non-rectangular display area, then the display area shape requirement is met, but the mask planarity deteriorates and evaporation precision is degraded
Solution Approach 1:
The mask system is segmented into two independent components: a rectangular fine metal mask and a non-rectangular shielding mask. The fine metal mask maintains a simple rectangular shape for high evaporation precision, while the shielding mask provides the non-rectangular shape definition. This segmentation allows each mask to optimize its function without compromising the other.
Solution Approach 2:
The shielding mask acts as an intermediary between the rectangular evaporation process and the desired non-rectangular display area. It is positioned between the fine metal mask and the substrate, mediating the evaporation pattern to achieve the target non-rectangular shape while maintaining process precision.
2Shape
If a non-rectangular shaped fine metal mask is designed, then the display area shape requirement is met, but the design and fabrication complexity increases
Solution Approach 1:
The complex non-rectangular shape requirement is segmented between two masks: the simple rectangular fine metal mask and the non-rectangular shielding mask. This division of shape complexity allows the fine metal mask to remain simple for easy fabrication, while the shielding mask absorbs the geometric complexity.
Solution Approach 2:
Instead of making the fine metal mask non-rectangular to match the display area, the invention inverts the approach by keeping the fine metal mask rectangular and using a shielding mask to create the non-rectangular pattern. This inversion simplifies the fine metal mask fabrication while achieving the desired display shape.
3Shape
If a non-rectangular shaped fine metal mask is used, then the display area shape is achieved, but the fitting in evaporation process deteriorates
Solution Approach 1:
The evaporation process is segmented into two stages: first, a rectangular evaporation pattern is deposited through the rectangular fine metal mask with excellent fitting; second, the shielding mask is used to define the final non-rectangular display area shape. This segmentation allows optimal fitting in the evaporation process while achieving the target shape.
Solution Approach 2:
The rectangular evaporation pattern is created as a preliminary action before the final shape definition. The fine metal mask first establishes a precise rectangular pattern that fits well in the evaporation process, and then the shielding mask refines this to the desired non-rectangular shape, ensuring optimal process fitting at each stage.
Data Source
AI summary
The disclosure discloses an organic electroluminescent display panel, a method for manufacturing the same, and a display device, where organic light-emitting layers of display sub-pixels and virtual sub-pixels may be created on an underlying substrate through evaporation using a fine metal mask and a shielding mask arranged in a stack, and the area of the organic light-emitting layer of a non-rectangular shaped virtual sub-pixel among the virtual sub-pixels is smaller than the area of the organic light-emitting layer of a display sub-pixel capable of emitting light in the same color.