Liquid Crystal Display Light Blocking Member and Spacer Integration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In liquid crystal displays, precise alignment of pixel electrodes and color filters on different panels is challenging, leading to potential alignment errors, and the increased size of light blocking members for maintaining cell gap uniformity can deteriorate the aperture ratio, necessitating an improved method for simultaneously forming light blocking and spacer elements.
Innovation Solution
A liquid crystal display design where a light blocking member with horizontal and vertical components is integrated with a sub-column spacer, overlapping a protrusion on the color filter, and a main column spacer is used to maintain the cell gap, with these elements formed using a two-tone mask to optimize alignment and aperture ratio.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If pixel electrodes and color filters are disposed on different display panels, then manufacturing flexibility is improved, but alignment precision deteriorates
Solution Approach 1:
The patent merges the color filter and pixel electrode onto the same display panel (TFT array panel), eliminating the need for precise alignment between separate panels. The color filter is formed directly on the TFT array panel in the same manufacturing process that forms the pixel electrode, ensuring inherent alignment accuracy while maintaining manufacturing flexibility.
Solution Approach 2:
The TFT array panel serves multiple functions: it acts as both the pixel electrode substrate and the color filter substrate. This multi-functional design eliminates the need for a separate common electrode panel, simplifying the overall structure and ensuring precise alignment between color filters and pixel electrodes through single-panel integration.
2Reliability
If the black matrix is enlarged to maintain bonding margin, then bonding reliability is improved, but aperture ratio deteriorates
Solution Approach 1:
The patent applies different properties to different regions of the light blocking member. The light blocking member has a first region with higher light blocking capability (for bonding margin) and a second region with lower light blocking capability (for aperture ratio). This local differentiation allows the light blocking member to maintain bonding reliability while minimizing impact on aperture ratio.
Solution Approach 2:
The patent changes the physical parameters of the light blocking member by forming it with a specific height range (50-200 nm) that is lower than conventional black matrices. This parameter change allows the light blocking member to provide sufficient bonding margin while occupying less area, thereby improving the aperture ratio.
3Device complexity
If multiple processes are used to simultaneously form light blocking member and spacers, then manufacturing complexity is reduced, but process difficulty increases
Solution Approach 1:
The patent segments the light blocking member formation into distinct regions (first region and second region) with different properties. This segmentation is achieved through a multi-tone mask that defines different exposure doses, allowing simultaneous formation of light blocking members and spacers with different characteristics in a single photolithography process, thereby reducing overall manufacturing complexity.
Solution Approach 2:
The patent introduces a multi-tone mask as an intermediary tool that enables simultaneous formation of light blocking members and spacers. The multi-tone mask has multiple transmittance regions that correspond to different pattern areas, acting as a mediator that translates a single exposure process into multiple distinct structural formations.
4Productivity
If a multi-tone mask is used for simultaneous formation, then manufacturing efficiency is improved, but material availability deteriorates
Solution Approach 1:
The patent changes the material parameter by using conventional photoresist materials with standard photolithography processes. Instead of requiring specialized multi-material systems, the invention achieves multi-region formation by controlling exposure parameters (dose, wavelength) and developing conditions, making the process compatible with existing manufacturing materials and improving material availability.
Data Source
AI summary
A liquid crystal display includes a lower substrate including a pixel area and a light blocking region, a thin film transistor layer on the lower substrate and including a gate line and a data line, a color filter on the thin film transistor layer and corresponding to the pixel area, a light blocking member on the color filter and corresponding to the light blocking region, an upper substrate facing the lower substrate, and a liquid crystal layer between the lower and upper substrates. The light blocking member includes a horizontal light blocking member extending along the gate line and a vertical light blocking member extending along the data line. The color filter includes a protrusion portion overlapping a portion of the horizontal light blocking member which is in the pixel area. A sub-column spacer includes the portion of the horizontal light blocking member overlapping the protrusion portion.