Liquid Crystal Display Columnar Spacers for Bubble Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional TFT-type liquid crystal display panels face challenges in maintaining a uniform cell gap and preventing bubble generation and color irregularities, especially when using the liquid-crystal dropping filling method, due to difficulties in controlling the height of second columnar members and irregularities in their formation during mass production.
Innovation Solution
The introduction of a display device design featuring first, second, and third columnar members with specific height and number relationships, where the third columnar members act as substitutes for the second members when their height is insufficient, and all are formed in a frusto-conical or frusto-pyramidal shape to maintain a uniform cell gap and prevent bubble generation and color irregularities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the liquid-crystal dropping filling method is used to improve productivity, then manufacturing efficiency is improved, but control over liquid crystal material quantity and cell gap uniformity deteriorates
Solution Approach 1:
The patent applies local quality by creating columnar members with different heights at different locations on the counter substrate. First columnar members have a first height in a first region, while second columnar members have a second height in a second region. This spatial variation in columnar member height allows localized control of cell gap to compensate for substrate deformation, thereby maintaining uniform liquid crystal material distribution and cell gap uniformity across the entire display panel while using the high-productivity dropping filling method.
2Manufacturing precision
If the number of columnar members is increased to suppress substrate deformation, then cell gap uniformity is improved, but bubble generation in liquid crystal material increases
Solution Approach 1:
The patent implements local quality by differentiating columnar member heights based on their spatial location. First columnar members with a first height are placed in a first region, while second columnar members with a second height are placed in a second region. This localized variation allows the patent to use a moderate total number of columnar members while achieving uniform cell gap control, thereby preventing the negative pressure and bubble generation that would result from using a large number of uniformly tall columnar members throughout the entire substrate.
3Object-generated harmful factors
If second columnar members are formed lower than first columnar members to prevent bubble generation, then bubble formation is reduced, but control precision over second columnar member height becomes difficult
Solution Approach 1:
The patent applies segmentation by dividing the columnar members into two distinct types: first columnar members with a first height and second columnar members with a second height. This segmentation allows each type to be optimized for its specific function - first columnar members provide structural support and deformation compensation, while second columnar members prevent bubble generation by maintaining appropriate spacing. The clear differentiation and separate optimization of these two segments makes height control more precise than attempting to optimize all columnar members uniformly.
Solution Approach 2:
The patent implements local quality by assigning different heights to columnar members based on their functional requirements and spatial locations. First columnar members in the first region have a first height optimized for deformation compensation, while second columnar members in the second region have a second height optimized for bubble prevention. This localized optimization of height parameters for different regions and functions enables precise control over the height of second columnar members, directly addressing the control precision difficulty mentioned in the contradiction.
4Productivity
If first columnar members and second columnar members are formed simultaneously by exposing and developing one photosensitive material film to improve productivity, then manufacturing efficiency is improved, but height control precision of second columnar members deteriorates
Solution Approach 1:
The patent applies segmentation by dividing the photosensitive material film into multiple functional regions that will form different types of columnar members. The photosensitive film is patterned such that when exposed and developed, it creates first columnar members in a first region and second columnar members in a second region. This segmentation of the photosensitive material allows simultaneous formation of multiple columnar member types with different heights in a single exposure-development cycle, achieving both high productivity and acceptable height control precision for mass production.
Solution Approach 2:
The patent implements local quality in the photosensitive material film by creating regions with different exposure characteristics or film properties. The photosensitive film is designed such that different regions respond differently to exposure, or have different initial properties that result in different developed heights. This localized differentiation of the photosensitive material enables the simultaneous formation of first and second columnar members with controlled height differences, resolving the contradiction between productivity and height control precision.
Data Source
AI summary
The generation of bubbles in a liquid crystal material of a liquid crystal display panel and the generation of color irregularities when the liquid crystal display panel is pushed can be reduced. In a display device having a liquid crystal display panel in which a liquid crystal material is filled between a first substrate and a second substrate, the second substrate forms, on a surface of an insulation substrate which faces the first substrate, first columnar members, second columnar members and third columnar members which differ from each other in a distance from the surface of the insulation substrate to a top portion of each columnar member. Assuming the distance of the first columnar member as L1, the distance of the second columnar member as L2 and the distance of the third columnar member as L3, a relationship among the distances L1, L3, L2 satisfies L1>L3>L2, and assuming the number of the first columnar members arranged on the surface of the insulation substrate as N1, the number of the second columnar members arranged on the surface of the insulation substrate as N2 and the number of the third columnar members arranged on the surface of the insulation substrate as N3, a relationship among the numbers N1, N2, N3 satisfies N2>N1>N3.