IPS LCD Array Substrate Electrode Alignment and Luminance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In-Plane Switching (IPS) mode LCD devices face issues with narrow viewing angles, low contrast ratio, and decreased image display quality due to misalignment and different material layers for common and pixel electrodes, which affect luminance and aperture ratio.
Innovation Solution
The array substrate design for IPS mode LCD devices includes a gate line and data line in perpendicular directions, with metal and common lines featuring protruding portions, and a thin film transistor connected to these lines, along with a common electrode and pixel electrode formed from the same transparent conductive material to prevent misalignment and enhance viewing angles and luminance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If common electrode and pixel electrode are formed using different material layers, then manufacturing process flexibility is improved, but misalignment occurs between electrodes reducing viewing angle and image quality
Solution Approach 1:
The patent merges the common electrode and pixel electrode into the same material layer (transparent conductive layer), forming them simultaneously through a single patterning process. This eliminates the misalignment issue that occurs when electrodes are formed in separate layers, while still allowing process flexibility through the use of standard transparent conductive materials like ITO.
Solution Approach 2:
The patent introduces protruding portions that extend in the third dimension (vertical direction) from the substrate plane. These protrusions allow the electrodes to maintain precise horizontal alignment while providing sufficient vertical separation for electrical insulation, resolving the conflict between alignment precision and manufacturing ease.
2Adaptability or versatility
If different material layers are used for common and pixel electrodes, then manufacturing adaptability is improved, but luminance and aperture ratio decrease
Solution Approach 1:
The patent uses the same transparent conductive material for both the common electrode and pixel electrode, ensuring homogeneous optical properties across both electrodes. This maximizes light transmission and luminance while maintaining the ability to selectively pattern electrodes through photolithography processes.
3Adaptability or versatility
If equal distances are maintained between all electrode portions, then viewing angle is improved, but manufacturing complexity increases
Solution Approach 1:
The patent segments the electrodes into multiple portions (first common portion, second common portions, first pixel portion, second pixel portions) with different geometries. The protruding portions create segmented structures that maintain equal distances in critical directions, improving viewing angle while the segmentation itself simplifies the manufacturing process by using standard photolithography patterning.
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 design improves the viewing angle and aperture ratio by maintaining equal distances between electrodes, preventing misalignment, and using transparent conductive materials to enhance luminance and image quality.
Implementation Method 1
a common electrode and a pixel electrode which are formed of a same transparent conductive material
Implementation Method 2
The liquid crystal layer is controlled by a horizontal electric field generated between the common electrode and the pixel electrode
Implementation Method 3
The liquid crystal molecules for the LCD device have unique characteristics, such that an arrangement direction (i.e., orientation) of the liquid crystal molecules can be controlled by applying a desired level of an electrical field to them
Implementation Method 4
an arrangement direction (i.e., orientation) of the liquid crystal molecules can be controlled by applying a desired level of an electrical field to them
Data Source
AI summary
An array substrate for an IPS mode LCD device includes a gate line in a first direction on a substrate and a data line in a second direction over the substrate; a metal and a common lines in the second direction on the substrate and includes a plurality of first and second protruding portions in the first direction, respectively; a TFT connected to the gate and data lines; an insulating layer over the metal and common lines; a common electrode over the insulating layer and including a first common portion in the second direction and a plurality of second common portions in the first direction; and a pixel electrode over the insulating layer and including a first pixel portion in the second direction and a plurality of second pixel portions in the first direction, wherein the plurality of second common and pixel portions are alternately arranged.