Display Device Black Matrix Step Difference Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices face issues with step differences in the black matrix, which can lead to deterioration of liquid crystal fluidity and shock absorbing properties, affecting image quality and panel reliability.
Innovation Solution
The design includes a display device with a black matrix and capping layer configuration that reduces step differences by positioning the black matrix in non-pixel areas and using a black column spacer, maintaining the integrity of liquid crystal fluidity and shock absorption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the black matrix is formed to cover the shielding electrode, then the shielding effect is improved, but the step difference increases causing liquid crystal fluidity deterioration
Solution Approach 1:
The patent divides the black matrix formation into two separate processes: first forming the black matrix in the non-pixel area to provide shielding, then forming a separate capping layer to cover the shielding electrode. This segmentation allows each layer to perform its specific function without creating harmful step differences that would affect liquid crystal fluidity.
Solution Approach 2:
The patent introduces a capping layer as an additional dimensional element between the shielding electrode and the black matrix. This extra layer fills the step difference created by the shielding electrode structure, creating a flat surface that prevents liquid crystal fluidity deterioration while maintaining the shielding function.
2Reliability
If the capping layer covers the shielding electrode completely, then the step difference is reduced, but the shielding effect in the crossing area is weakened
Solution Approach 1:
The patent applies different properties to different areas of the capping layer. In the crossing area where the first and second non-pixel areas intersect, the capping layer is intentionally not formed, allowing the black matrix to directly cover the shielding electrode for maximum shielding effect. In other areas, the capping layer is formed to reduce step differences and protect liquid crystal fluidity.
3Object-affected harmful factors
If the black matrix height is increased to improve shielding, then the step difference increases causing shock absorbing property deterioration
Solution Approach 1:
The patent introduces a black column spacer as a cushioning element between the black matrix and the substrate. This spacer compensates for the step difference created by the black matrix structure, providing a gradual transition that maintains shock absorbing properties while allowing the black matrix to maintain its shielding function.
Data Source
AI summary
A display device includes pixels. At least one of the pixels includes a pixel area, a first non-pixel area disposed adjacent to the pixel area and extending in a first direction, and a second non-pixel area extending in a second direction substantially perpendicular to the first direction. The pixel including a pixel area includes a pixel electrode disposed in the pixel area, a color filter extending in the second direction, and a shielding electrode extending in the second direction and disposed on the color filter in the second non-pixel area. A capping layer is disposed on the color filter. The capping layer covers the shielding electrode in an area except for a crossing area where the first and second non-pixel areas cross each other. A black matrix is disposed on the capping layer and the shielding electrode in the first non-pixel area.