Liquid Crystal Display Wire End Shaping for Light Leakage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Transmission-type liquid crystal displays suffer from light leakage due to depolarization at the edges of metallic wires, which reduces contrast and numerical aperture, and existing solutions like light-shielding masks or phase plates either lower brightness or increase manufacturing costs.
Innovation Solution
The polarizing plate's axis of linear polarization is slanted relative to the scan lines, and the metallic wire edges are shaped to be parallel or perpendicular to this axis, preventing depolarization and eliminating the need for additional light-shielding masks, thus maintaining a high numerical aperture.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a light-shielding black mask is provided on the counter substrate to prevent light leakage, then light leakage is reduced, but the effective area (aperture area) of pixels is restricted, lowering numerical aperture and brightness
Solution Approach 1:
The patent extracts the light-shielding function from the counter substrate's black mask and relocates it to the array substrate's metallic wire structure. By shaping the metallic wire ends to be parallel or perpendicular to the polarization axis, the wire itself becomes the light-shielding element, eliminating the need for the counter substrate's black mask and preserving the full aperture area.
Solution Approach 2:
Instead of adding a light-shielding layer on the counter substrate (conventional approach), the patent inverts the approach by modifying the metallic wire structure on the array substrate to perform the light-shielding function. This inversion eliminates the need for additional components and maintains maximum aperture area.
2Reliability
If metallic wires are formed in the transmission area to connect pixel electrode and thin film transistor, then electrical connection is achieved, but linearly polarized light is shielded and depolarization occurs at wire ends, causing light leakage
Solution Approach 1:
The patent applies local quality by giving specific directional characteristics to the metallic wire ends. The wire ends are shaped to be parallel or perpendicular to the polarization axis of the polarizing plate, creating localized optical properties that prevent depolarization while maintaining the wire's electrical connection function.
Solution Approach 2:
The patent introduces asymmetry in the metallic wire structure by controlling the orientation of wire ends relative to the polarization axis. This asymmetric configuration (parallel or perpendicular orientation) is specifically designed to prevent depolarization, distinguishing it from conventional symmetric wire structures.
3Object-affected harmful factors
If a phase plate is arranged and circular polarization is utilized to prevent light leakage, then light leakage is restrained, but manufacturing cost is raised and transmittance is lowered
Solution Approach 1:
The patent replaces expensive phase plates with a simple geometric modification of existing metallic wires. The wire ends are shaped to be parallel or perpendicular to the polarization axis, creating an effective light-shielding solution without requiring additional costly components like phase plates.
Solution Approach 2:
The metallic wires, which are already present in the display structure for electrical connection, are made to serve dual purposes: electrical connection and light shielding. By shaping the wire ends appropriately, the existing wire structure itself performs the light-shielding function without requiring separate phase plate components.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration effectively prevents light leakage while maintaining a high numerical aperture, enhancing the display's contrast and brightness without increasing manufacturing costs.
Implementation Method 1
The polarizing plate converts incident light, coming externally (for instance, from an illuminating backlight), into linearly polarized light
Implementation Method 2
The liquid crystal controls the transmission condition of the linearly polarized light according to a voltage
Implementation Method 3
the linearly polarized light reflected and diffracted at the end surface is disturbed in polarization state
Implementation Method 4
the linearly polarized light reflected and diffracted at the end surface is disturbed in polarization state
Data Source
AI summary
A liquid crystal display including a polarizing plate having a linear polarization axis slanted in relation to a scan line, a transparent pixel electrode, an active element which drives the transparent pixel electrode, and a wire for connecting the active element and the transparent pixel electrode. The wire has an end part so shaped as to be slanted in a direction parallel to or perpendicular to the linear polarization axis.