Series-Parallel LED Pixel Layout for Higher Display Emission

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The emission efficiency of display devices is not improved due to a low ratio of light emitting elements connected in series between pixel electrodes, limiting the overall performance of the light emitting apparatus.

Innovation Solution

A display device design that connects light emitting elements in a combination of series and parallel configurations, with specific semiconductor layer structures and electrode arrangements to enhance emission efficiency, including the use of n-type and p-type semiconductor layers and insulative films to prevent short circuits and improve light emission.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If light emitting elements are connected in parallel between pixel electrodes, then the device complexity is reduced, but the emission efficiency does not improve

Engineering Contradiction:
Improveconnection structureVSAvoidemission efficiency
Core Design Contradiction:
Device complexityVSProductivity

Solution Approach 1:

The pixel electrode is divided into multiple sub-pixel electrodes, and light emitting elements are arranged in series between these segmented electrodes. This segmentation allows the light emitting elements to be connected in series while maintaining a compact structure, thereby improving emission efficiency without significantly increasing device complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transitions from a two-dimensional parallel connection layout to a three-dimensional arrangement where light emitting elements are stacked vertically between pixel electrodes. This dimensional change enables series connection of multiple light emitting elements within the same pixel area, improving emission efficiency while maintaining reasonable device complexity.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Productivity

If light emitting elements are connected in series between pixel electrodes, then the emission efficiency is improved, but the device complexity increases

Engineering Contradiction:
Improveemission efficiencyVSAvoidconnection structure
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

Multiple light emitting elements are merged into a single pixel structure by connecting them in series between pixel electrodes. This merging approach allows the series connection configuration to be integrated within the pixel structure, improving emission efficiency while controlling device complexity through unified design.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

Light emitting elements are nested within the pixel electrode structure, with multiple elements arranged in series between the electrodes. This nesting configuration allows series connection of multiple elements within a compact pixel structure, improving emission efficiency without proportionally increasing device complexity.

Inventive Principle:
Principle #7Nested doll (Nesting)

3Productivity

If more light emitting elements are arranged in series, then the emission efficiency is improved, but the risk of short circuits increases

Engineering Contradiction:
Improveemission efficiencyVSAvoidshort circuit risk
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

Insulative films are introduced as intermediary layers between adjacent light emitting elements and between the light emitting elements and pixel electrodes. These intermediary insulative films prevent direct contact and potential short circuits, allowing more elements to be connected in series while maintaining reliability and improving emission efficiency.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

Insulative films are selectively applied at specific locations where short circuit risks exist, such as between adjacent light emitting elements and at contact points with pixel electrodes. This localized quality enhancement prevents short circuits without adding unnecessary complexity throughout the entire structure, enabling series connection of multiple elements for improved emission efficiency.

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

The proposed design significantly enhances the emission efficiency of the display device by optimizing the connection configuration and material structures, leading to improved light output and device performance.

Implementation Method 1

at least one first light emitting element located between the first electrode and the second electrode, at least one second light emitting element located between the second electrode and the third electrode

Methodology Applied
Scientific EffectElectroluminescence: Electroluminescence

Implementation Method 2

an insulative film between the first light emitting element and the second light emitting element

Methodology Applied
Scientific EffectElectrical insulation: Electrical Resistance

Data Source

PatentEP3866196B1Display device
Publication Date: 2024.02.21 SAMSUNG DISPLAY CO LTD
  • EP3866196B1 patent drawingFigure 1A~1B
  • EP3866196B1 patent drawingFigure 2A~2B
  • EP3866196B1 patent drawingFigure 3A~3B

AI summary

A display device includes a substrate. A first electrode, a second electrode, and a third electrode are on the substrate, and are sequentially arranged along a first direction. A first light emitting element is located between the first electrode and the second electrode. A second light emitting element is located between the second electrode and the third electrode. A first contact electrode overlaps the first electrode and one end of the first light emitting element, and is in contact with the first electrode and the one end of the first light emitting element. A second contact electrode overlaps and is in contact with the other end of the first light emitting element. A third contact electrode overlaps and is in contact with the second electrode and the other end of the second light emitting element. The second contact electrode extends while detouring the third contact electrode.