Anode Line Layout for Uniform Low-Gray Inorganic LED Displays

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In display devices using inorganic light-emitting diodes, parasitic capacitance due to capacitive coupling between anode lines and metal lines leads to luminance differences in central and peripheral areas during low-gray light emission, causing column line mura and increased power consumption.

Innovation Solution

Anode lines are designed to be repeatedly bent in a zigzag manner along the column direction, overlapping with metal or signal lines to equalize capacitance values, preventing luminance variations and reducing power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If anode lines are arranged with regular spacing in the display area, then the layout is simple and manufacturing is easy, but capacitance differences occur between central and peripheral areas causing luminance non-uniformity

Engineering Contradiction:
Improveanode line layout simplicityVSAvoidluminance uniformity
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent applies local quality by making different portions of the anode line have different shapes. Specifically, anode lines in the central area are designed with bent portions that extend in the row direction, while anode lines in peripheral areas maintain straight configurations. This local differentiation compensates for capacitance differences, ensuring uniform luminance across the display area while maintaining manufacturing feasibility.

Inventive Principle:
Principle #3Local quality

2Device complexity

If anode lines are made straight with regular spacing, then device complexity is low, but capacitance variation causes column line mura and requires complex compensation

Engineering Contradiction:
Improveanode line structureVSAvoiddisplay quality
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent implements local quality by differentiating anode line shapes based on their position. Central area anode lines include bent portions extending in the row direction to increase capacitance, while peripheral anode lines remain straight. This localized structural modification equalizes capacitance values across different areas, preventing column line mura and improving display reliability without requiring complex external compensation circuits.

Inventive Principle:
Principle #3Local quality

3Manufacturing precision

If anode lines are bent in zigzag manner in central area, then capacitance is equalized across display area, but anode line structure becomes more complex

Engineering Contradiction:
Improveluminance uniformityVSAvoidanode line configuration
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent applies local quality by restricting the bent configuration to only central area anode lines, while peripheral anode lines remain straight. This targeted approach equalizes capacitance values across the display area, achieving uniform luminance. The complexity is minimized by applying the bent structure only where needed rather than uniformly across all anode lines.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent segments the anode line structure into different types based on position: straight anode lines for peripheral areas and bent anode lines with extended portions for central areas. This segmentation allows each segment to be optimized for its specific location, equalizing capacitance values while managing overall structural complexity in a systematic manner.

Inventive Principle:
Principle #1Segmentation

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 capacitance differences, preventing mura and reducing power consumption, thereby extending the lifespan and improving the quality of the display device.

Implementation Method 1

an anode line that applies an anode voltage to each light-emitting element generates parasitic capacitance due to capacitive coupling with a metal line disposed in a different layer from a layer of the anode line

Methodology Applied
Scientific EffectCapacitive coupling: Capacitance

Data Source

PatentEP4685779A1Display device
Publication Date: 2026.01.28 LG DISPLAY CO LTD
  • EP4685779A1 patent drawingFigure 1
  • EP4685779A1 patent drawingFigure 2
  • EP4685779A1 patent drawingFigure 3

AI summary

The present disclosure is a display device. The display device includes a substrate including a display area and a non-display area; a pixel driving circuit disposed on the substrate in the display area; a plurality of light-emitting elements electrically connected to the pixel driving circuit; and a plurality of anode lines extending in a column direction and arranged in a row direction, wherein each of the anode line connects anode electrodes of light-emitting elements arranged so as to be adjacent to each other in the column direction among the plurality of light-emitting elements, wherein each of some of the plurality of anode lines spaced apart from the pixel driving circuit by a predetermined distance in the row direction is repeatedly bent in a zigzag manner and extends along the column direction.