Flexible Display Panel Stress Relief Layer Design

Solution Overview

Problem

Flexible display panels with plastic substrates face reduced lifespan due to repetitive bending or rolling, as existing technologies fail to effectively distribute stress and prevent structural damage.

Innovation Solution

A display panel design featuring a thin film transistor substrate with a stress relief layer having support patterns and stress relief patterns of lower density, along with a barrier and buffer layer, to alleviate stress and prevent concentration of strain during bending or rolling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a flexible substrate is used to enable mobile and foldable display devices, then the display panel achieves light weight and thin film properties, but the lifespan is reduced due to repetitive bending or rolling

Engineering Contradiction:

ImproveflexibilityVSAvoidlifespan

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The stress relief layer is divided into multiple support patterns spaced apart from each other, creating segmented regions that can independently manage stress. This segmentation allows the structure to flex while distributing mechanical stress across multiple discrete support points rather than a continuous layer, thereby maintaining flexibility while reducing stress concentration during repetitive bending.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The stress relief layer exhibits local quality variations through different pattern densities - support patterns in regions requiring structural strength and stress relief patterns in regions requiring stress distribution. This spatial variation in pattern density allows different regions of the same layer to serve different functions, optimizing both flexibility and lifespan simultaneously.

Inventive Principle:

Principle #3Local quality

2Strength

If the stress relief layer uses high density patterns, then structural strength is improved, but stress concentration occurs during bending

Engineering Contradiction:

Improvestructural strengthVSAvoidstress concentration

Core Design Contradiction:

StrengthVSStress or pressure

Solution Approach 1:

The stress relief layer is divided into multiple support patterns spaced apart from each other, creating segmented regions that can independently manage stress. This segmentation allows the structure to flex while distributing mechanical stress across multiple discrete support points rather than a continuous layer, thereby maintaining flexibility while reducing stress concentration during repetitive bending.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The stress relief layer exhibits local quality variations through different pattern densities - support patterns in regions requiring structural strength and stress relief patterns in regions requiring stress distribution. This spatial variation in pattern density allows different regions of the same layer to serve different functions, optimizing both flexibility and lifespan simultaneously.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS9755184B2Display panel and method of fabricating the same

Publication Date: 2017.09.05 SAMSUNG DISPLAY CO LTD

AI summary

A display panel includes a thin film transistor substrate and a display layer disposed on the thin film transistor substrate and having a display. The thin film transistor substrate may include a base substrate, a stress relief layer disposed on the base substrate and including at least one stress relief pattern, and a driver layer disposed on the stress relief layer and including at least one thin film transistor coupled to the display.