LCD Electrode Cutouts for Fringe Field Alignment

Solution Overview

Problem

The manufacturing of vertically aligned liquid crystal displays (LCDs) with improved transmittance and controllability is hindered by the need for additional processing steps and equipment, increasing costs and complexity due to the requirement of an alignment aid and its curing process.

Innovation Solution

The design incorporates a lower panel electrode with a center electrode and minute branches, and an upper panel electrode with specific cutouts, which generate fringe fields to align liquid crystal molecules without the need for a pretilt alignment aid, allowing for controlled liquid crystal alignment and increased transmittance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an alignment aid and curing process are used to provide pretilt to liquid crystal molecules, then liquid crystal controllability and response speed are improved, but manufacturing cost increases and manufacturing process becomes complicated

Engineering Contradiction:

Improveliquid crystal controllabilityVSAvoidmanufacturing process complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent removes the alignment aid layer and curing process from the manufacturing system. Instead of using external alignment aids, the electrode patterns themselves generate fringe fields that directly control liquid crystal alignment, eliminating the need for separate alignment aid materials and UV curing steps.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The electrode structure performs dual functions: it generates the electric field for liquid crystal switching and simultaneously provides the fringe field for liquid crystal alignment. The electrode patterns serve their own alignment function, eliminating the need for separate alignment aids.

Inventive Principle:

Principle #25Self-service

2Reliability

If an alignment aid and curing process are used to provide pretilt to liquid crystal molecules, then liquid crystal controllability is improved, but manufacturing cost increases

Engineering Contradiction:

Improveliquid crystal controllabilityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent removes the alignment aid layer and curing process from the manufacturing system. Instead of using external alignment aids, the electrode patterns themselves generate fringe fields that directly control liquid crystal alignment, eliminating the need for separate alignment aid materials and UV curing steps.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The electrode structure performs dual functions: it generates the electric field for liquid crystal switching and simultaneously provides the fringe field for liquid crystal alignment. The electrode patterns serve their own alignment function, eliminating the need for separate alignment aids.

Inventive Principle:

Principle #25Self-service

3Ease of manufacture

If conventional electrode patterns are used without cutouts, then manufacturing is simpler, but liquid crystal alignment and domain formation are insufficient

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidliquid crystal alignment precision

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent divides the electrode into multiple segments with cutouts (first cutout, second cutout, third cutout) that create distinct regions. These segmented electrode patterns generate localized fringe fields that precisely control liquid crystal alignment in different domains, achieving both manufacturing simplicity and alignment precision.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The electrode pattern has different structures in different regions: cutouts are strategically placed to create specific fringe field distributions in different domains. This local variation in electrode structure enables precise control of liquid crystal alignment direction in each domain while maintaining overall manufacturing simplicity.

Inventive Principle:

Principle #3Local quality

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 approach simplifies the manufacturing process, reduces costs, and enhances liquid crystal controllability and transmittance by eliminating the need for additional equipment and processing steps, while stabilizing liquid crystal texture and improving side visibility.

Implementation Method 1

the plurality of domains may be formed by aligning the liquid crystal molecules by a fringe field generated between edges of the cutouts and the field generating electrodes facing the edges thereof

Methodology Applied

Scientific EffectFringe field: Electric Field

Data Source

PatentUS10782564B2Liquid crystal display

Publication Date: 2020.09.22 LONESTAR CRYSTAL DISPLAY LLC

AI summary

A liquid crystal display includes a lower panel electrode including a lower panel unit electrode, an upper panel electrode including an upper panel unit electrode facing the lower panel unit electrode, and a liquid crystal layer between the lower panel electrode and the upper panel electrode and including liquid crystal molecules, where the lower panel unit electrode includes a center electrode disposed at a center thereof, minute branches which extends from an edge side of the center electrode to an outside, and a first cutout is defined in the center of the center electrode, and the a second cutout is defined in the upper panel unit electrode between the minute branches and the first cutout, and a third cutout is connected to the second cutout and defines a boundary between subregions together with the first cutout.