Liquid Crystal Display Panel Capacitance Adjusting Layer Greenish Frame
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Liquid crystal display panels exhibit a greenish frame issue due to unbalanced polarity inversion driving methods, where the common voltage is affected by data signals to red and blue sub-pixels, leading to reduced pixel voltage differences and distorted gray scales.
Innovation Solution
The implementation of capacitance adjusting layers with different dielectric constants between the common electrode and data lines for each sub-pixel type, ensuring equalization of common voltage offsets and maintaining net common voltage stability, thereby balancing pixel voltages across red, green, and blue sub-pixels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If column inversion driving method is used to drive liquid crystal display panel, then polarity inversion is achieved to prevent permanent deformation of liquid crystal molecules, but common voltage is affected by data signals to red and blue sub-pixels causing greenish frame issue
Solution Approach 1:
The patent applies local quality by introducing different capacitance adjusting layers with different dielectric constants for different sub-pixel types (red, green, blue). Specifically, a first capacitance adjusting layer with a first dielectric constant is provided for red and blue sub-pixels, while a second capacitance adjusting layer with a second dielectric constant is provided for green sub-pixels. This local differentiation compensates for the unequal capacitance effects caused by column inversion driving, thereby eliminating the greenish frame issue while maintaining the polarity inversion benefits.
2Reliability
If data signals are provided to red and blue sub-pixels at high voltage level, then positive polarity is achieved for these sub-pixels, but common voltage shifts toward high voltage level reducing pixel voltage difference for red/blue sub-pixels
Solution Approach 1:
The patent applies parameter changes by modifying the capacitance values of the coupling capacitors through the introduction of capacitance adjusting layers with different dielectric constants. The first capacitance adjusting layer has a first dielectric constant that is different from the second dielectric constant of the second capacitance adjusting layer. This parameter modification balances the voltage division ratios in the voltage divider circuits formed by the coupling capacitors and liquid crystal capacitors, thereby compensating for the common voltage shift and maintaining precise pixel voltage differences for all sub-pixel types.
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 solution effectively balances the common voltage shifts caused by data signals, eliminating the greenish frame issue by ensuring consistent voltage differences between the common electrode and sub-pixel electrodes, thus improving display quality.
Implementation Method 1
The first capacitance adjusting layer is disposed between the common electrode layer and the second data line, and the first capacitance adjusting layer has a second dielectric constant, and the second dielectric constant is larger than the first dielectric constant
Data Source
AI summary
A liquid crystal display panel includes a first substrate, a second substrate, a liquid crystal layer disposed between the first substrate and the second substrate, a common electrode layer disposed on the first substrate and a plurality of pixel structures disposed on the second substrate. Each of the pixel structure includes a first data line, a second data line, a third data line and at least a capacitance adjusting layer. The capacitance adjusting layer is disposed between the common electrode layer and the second data line.