LCD Common Voltage Adjustment via Coupling Line Crosstalk Suppression

Solution Overview

Problem

Liquid crystal displays (LCDs) experience crosstalk due to parasitic capacitors between pixel electrodes and the common electrode layer, which affects the common voltage and results in reduced performance.

Innovation Solution

A liquid crystal display with a common voltage generator connected to a coupling line, which adjusts common voltages based on influence signals generated by data signals applied to the data lines, thereby reducing or eliminating crosstalk by applying different common voltages to divided regions of the common electrode layer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If data signals are applied to data lines, then pixel units can display gray levels, but crosstalk occurs due to parasitic capacitors affecting common voltage

Engineering Contradiction:

Improvedisplay performanceVSAvoidcrosstalk

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The common electrode layer is divided into multiple regions, with each region having an independent common voltage generator. This segmentation allows each region to independently adjust its common voltage to compensate for crosstalk caused by data signals, while maintaining overall display performance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent implements a feedback mechanism where the common voltage generator adjusts the common voltage based on the influence signal generated by data signals. This feedback loop compensates for voltage changes caused by parasitic capacitors, thereby reducing crosstalk.

Inventive Principle:

Principle #23Feedback

2Device complexity

If a single common voltage is applied to the common electrode layer, then the structure is simple, but crosstalk cannot be suppressed

Engineering Contradiction:

Improvevoltage generation structureVSAvoidcrosstalk

Core Design Contradiction:

Device complexityVSObject-affected harmful factors

Solution Approach 1:

The common electrode layer is divided into multiple regions, with each region having an independent common voltage generator. This segmentation allows each region to independently adjust its common voltage to compensate for crosstalk caused by data signals, while maintaining overall display performance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the common electrode layer are assigned different common voltages tailored to their specific requirements. This local quality approach allows each region to optimize its performance and suppress crosstalk independently, rather than using a uniform voltage across the entire electrode layer.

Inventive Principle:

Principle #3Local quality

3Object-affected harmful factors

If common voltage is adjusted to suppress crosstalk, then display performance improves, but voltage differences across common electrode layer increase

Engineering Contradiction:

Improvecrosstalk suppressionVSAvoidvoltage difference

Core Design Contradiction:

Object-affected harmful factorsVSStress or pressure

Solution Approach 1:

Different regions of the common electrode layer are assigned different common voltages tailored to their specific requirements. This local quality approach allows each region to optimize its performance and suppress crosstalk independently, rather than using a uniform voltage across the entire electrode layer.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent dynamically adjusts the common voltage parameter in different regions based on the influence signals generated by data signals. This parameter change allows the system to suppress crosstalk while managing voltage differences through adaptive control.

Inventive Principle:

Principle #35Parameter changes

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 solution effectively suppresses crosstalk between data lines, improving the overall performance and reducing voltage differences across the common electrode layer by precisely adjusting common voltages according to the influence signals.

Implementation Method 1

parasitic capacitors between pixel electrodes and the common electrode layer, which affects the common voltage

Methodology Applied

Scientific EffectParasitic capacitance: Parasitic Capacitance

Data Source

PatentUS8106869B2Liquid crystal display with coupling line for adjusting common voltage and driving method thereof

Publication Date: 2012.01.31 RED OAK INNOVATIONS LTD

AI summary

An exemplary liquid crystal display includes parallel data lines, a data driver configured for driving the data lines, a coupling line crossing the data lines, a common electrode layer, and a common voltage generator configured for applying common voltages to the common electrode layer. The common voltage generator is connected to the coupling line. When data driver applies a plurality of data signals to the data lines, the data signals generate an influence signal at the coupling line. The common voltage generator adjusts common voltages applied to the common electrode layer according to the influence signal. A related method for driving the liquid crystal display is also provided.