Intersecting Common Electrode Layout for Low-Refresh LCD Flicker
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Liquid crystal display devices with low refresh rates experience flicker issues due to significant changes in pixel transmittance, leading to reduced display quality, increased power consumption, and light leakage, while also facing challenges with parasitic capacitance and aperture ratio.
Innovation Solution
A display device design featuring a common electrode with intersecting regions that differ in orientation from the signal and pixel electrodes, reducing alignment interference and maintaining constant transmittance, along with a capacitor structure for increased charge capacity and reduced parasitic capacitance, utilizing oxide semiconductor films for improved electrical characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the refresh rate is lowered to reduce power consumption, then power consumption is reduced, but pixel transmittance changes significantly causing flicker and reduced display quality
Solution Approach 1:
A capacitor is connected to the pixel electrode to pre-store charge and maintain the voltage applied to the liquid crystal during the hold period between refresh cycles. This preliminary charge storage action enables the pixel transmittance to be maintained constant throughout the display period, preventing flicker even at low refresh rates.
Solution Approach 2:
The invention changes the electrical parameter (voltage) applied to the pixel electrode by using a capacitor to maintain a constant voltage level during the hold period. This parameter stabilization ensures that pixel transmittance remains constant, eliminating flicker while enabling low refresh rate operation.
2Illumination intensity
If the aperture ratio is increased to improve display brightness, then light transmission is improved, but parasitic capacitance increases causing wiring delay
Solution Approach 1:
The common electrode is divided into multiple regions with different extending directions. Specifically, a first region extends in a first direction and a second region extends in a second direction that intersects with the first direction. This segmentation reduces the overlapping area between the common electrode and signal lines, thereby reducing parasitic capacitance while maintaining a large aperture ratio.
Solution Approach 2:
The common electrode employs an asymmetric design where different regions have different orientations relative to the signal lines. This asymmetric configuration minimizes the overlapping area between the common electrode and signal lines in critical regions, reducing parasitic capacitance effects while preserving overall aperture ratio.
3Ease of manufacture
If the common electrode extends parallel to signal lines to simplify manufacturing, then manufacturing is simplified, but parasitic capacitance increases causing wiring delay
Solution Approach 1:
The common electrode is segmented into multiple regions with different orientations. The first region extends in a first direction and the second region extends in a second direction that intersects with the first direction. This segmentation strategy reduces the overlapping area between the common electrode and signal lines, thereby reducing parasitic capacitance while maintaining manufacturing feasibility.
4Device complexity
If the overlap area between common electrode and signal lines is reduced to decrease parasitic capacitance, then wiring delay is reduced, but manufacturing complexity increases
Solution Approach 1:
The common electrode is divided into a first region extending in a first direction and a second region extending in a second direction that intersects with the first direction. This segmentation reduces the overlapping area between the common electrode and signal lines, thereby reducing parasitic capacitance and wiring delay while maintaining reasonable manufacturing complexity.
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
The design effectively minimizes flicker, enhances display quality, reduces power consumption, and increases aperture ratio, while maintaining low refresh rates and efficient charge handling.
Implementation Method 1
alignment of liquid crystal molecules is controlled by applying an electric field generated between the pixel electrode and a common electrode to the liquid crystal in the opening
Implementation Method 2
maintaining charge stored between electrodes, so that transmittance of a pixel can be held
Data Source
AI summary
To provide a display device with excellent display quality, in a display device including a signal line, a scan line, a transistor, a pixel electrode, and a common electrode in a pixel, the common electrode is included in which an extending direction of a region overlapping with the signal line differs from an extending direction of a region overlapping with the pixel electrode in a planar shape and the extending directions intersect with each other between the signal line and the pixel electrode. Thus, a change in transmittance of the pixel can be suppressed; accordingly, flickers can be reduced.