Color Filter Substrate With Selective Protective Films
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The formation of stepped portions between pixels in color filters of liquid crystal display devices leads to distorted electric fields, decreased contrast, and increased color differences, necessitating additional processing steps that raise production costs and introduce defects.
Innovation Solution
A color filter substrate with transparent protective films formed on sub-pixels, where the height difference between the films and the reference plane is less than 0.1 μm, with edges positioned at secondary inflection points to prevent impurity adherence and eliminate the need for additional processing, featuring a transmittance of 85% or higher.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a transparent organic thin film is formed over the entire surface of the color filter to reduce stepped portion height, then the height difference is reduced, but impurities adhere to the thin film increasing defects
Solution Approach 1:
The patent divides the color filter surface into multiple regions: stepped portions between pixels and plateau portions (sub-pixels). Transparent protective films are selectively formed only on the plateau portions, not on the entire surface. This segmentation approach maintains the height reduction benefit while minimizing the surface area exposed to impurities, thereby reducing defect formation.
Solution Approach 2:
The patent applies different treatments to different regions of the color filter. Transparent protective films are applied locally to plateau portions where they are needed for height reduction, while stepped portions are left untreated or treated differently. This local quality approach ensures that impurity adhesion is minimized by limiting the film formation area, while still achieving the desired height reduction effect in critical regions.
2Manufacturing precision
If additional processing steps are implemented to compensate for stepped portions, then contrast is improved, but production cost increases
Solution Approach 1:
The patent performs preliminary action by forming transparent protective films on the plateau portions during the color filter manufacturing process itself, before the liquid crystal cell assembly is complete. This preliminary height reduction eliminates the need for subsequent optical compensation films or circuit signal compensation, thereby reducing production costs while maintaining contrast.
3Reliability
If extreme cleanliness conditions are maintained to prevent impurity adhesion, then defect rate is reduced, but production complexity and cost increase
Solution Approach 1:
The patent extracts or removes the problematic entire-surface film formation step and replaces it with selective film formation only on plateau portions. This extraction of the unnecessary full-surface coating step reduces the area vulnerable to impurity adhesion, thereby lowering defect rates without requiring extreme cleanliness conditions throughout the entire production process.
Data Source
AI summary
A color filter substrate is provided. In the color filter substrate, transparent protective films are formed on respective sub-pixels of a color filter. The color filter substrate has improved electric field characteristics without the need for additional optical or circuit compensation to achieve an improvement in contrast and a reduction in color difference.