OLED Panel Sub-Pixel Segmentation for Defect Isolation

Solution Overview

Problem

Organic light emitting display devices face issues with sub-pixel defects due to transistor deterioration or internal shorts, leading to abnormal operation, where either darkening or brightening occurs, making it difficult to achieve natural colors and potentially shorting the circuit and light emitting parts, especially when attempting to repair defects using algorithms.

Innovation Solution

The design includes a pixel configuration with multiple sub-pixels, each driven by a single circuit part that can separately control multiple light emitting parts, allowing for the isolation and normal operation of unaffected parts even if one sub-pixel experiences a defect, thereby preventing misapplication and maintaining color accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If a single circuit part drives multiple light emitting parts, then the aperture ratio and visibility are improved, but the complexity of controlling and isolating individual parts increases

Engineering Contradiction:

Improveaperture ratioVSAvoidcircuit control complexity

Core Design Contradiction:

Area of stationary objectVSDevice complexity

Solution Approach 1:

The light emitting part is divided into multiple sub-regions (first light emitting part and second light emitting part), each controlled by separate switching elements (first and second switching transistors). This segmentation allows independent control and isolation of defective regions while maintaining overall system functionality.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The circuit employs dynamic control mechanisms where switching transistors can selectively connect or disconnect different light emitting parts based on operational needs. This dynamic switching capability enables the circuit to adapt to defects by isolating problematic regions while maintaining control over the entire display panel.

Inventive Principle:

Principle #15Dynamics

2Illumination intensity

If multiple light emitting parts are controlled by a single circuit part, then the visibility is enhanced, but the reliability decreases when one part defects

Engineering Contradiction:

ImprovevisibilityVSAvoiddefect tolerance

Core Design Contradiction:

Illumination intensityVSReliability

Solution Approach 1:

The light emitting part is divided into multiple sub-regions (first light emitting part and second light emitting part), each controlled by separate switching elements (first and second switching transistors). This segmentation allows independent control and isolation of defective regions while maintaining overall system functionality.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The circuit design incorporates redundant switching transistors and separate control paths for different light emitting parts. When a defect occurs in one part, the corresponding switching transistor can be deactivated to isolate the defect, preventing it from affecting other parts and cushioning against total failure.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Reliability

If sub-pixel defects occur due to transistor deterioration or internal shorts, then darkening or brightening occurs, but the ability to repair using algorithms decreases

Engineering Contradiction:

Improvenormal operationVSAvoiddefect repairability

Core Design Contradiction:

ReliabilityVSEase of repair

Solution Approach 1:

The light emitting part is divided into multiple sub-regions (first light emitting part and second light emitting part), each controlled by separate switching elements (first and second switching transistors). This segmentation allows independent control and isolation of defective regions while maintaining overall system functionality.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

When a defect is detected in a specific light emitting part, the corresponding switching transistor is deactivated to extract or isolate the defective region from the operational circuit. This prevents the defect from affecting other parts and allows the system to continue functioning with reduced capability rather than complete failure.

Inventive Principle:

Principle #2Taking out (Extraction)

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 configuration enables the normal operation of unaffected light emitting parts when defects occur, improving color reproduction and reducing the occurrence of dark spots, enhancing the visibility and aperture ratio of the display panel.

Implementation Method 1

an organic light emitting element which includes a first electrode connected to the driving transistor, an organic light emitting layer, and a second electrode

Methodology Applied

Scientific EffectElectroluminescence: Electroluminescence

Data Source

PatentUS10665158B2Organic light emitting display panel, organic light emitting display device, and repairing method of the same

Publication Date: 2020.05.26 LG DISPLAY CO LTD

AI summary

Discussed is a panel including: a plurality of pixels, each pixel including a plurality of sub-pixels; and a single circuit part, wherein at least one of the plurality of sub-pixels in the each pixel has a plurality of emitting parts that are all light emitting, and wherein the single circuit part is connected to the plurality of emitting parts to drive the plurality of emitting parts to all emit light.