Flexible Display Window Layering for Hardness and Folding Reliability

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing flexible display devices face challenges in maintaining mechanical properties while achieving excellent folding characteristics, as conventional windows often deteriorate during bending or folding operations.

Innovation Solution

A display device with a window structure comprising a base layer, a high refractive layer made of a first base resin and inorganic particles, and a low refractive layer made of inorganic particles, alternately arranged with an adhesive and buffer layers, enhancing surface hardness and folding reliability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a conventional window structure is used in flexible display devices, then the device can maintain basic mechanical properties, but the window deteriorates during folding or bending operations

Engineering Contradiction:

Improvefolding characteristicsVSAvoidmechanical properties

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The window is divided into multiple functional layers including a base layer, hard coating layer, high refractive layer, and low refractive layer. Each layer serves a specific function: the base layer provides structural support, the hard coating layer enhances surface durability, and the refractive layers optimize optical properties while maintaining flexibility.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The window employs composite material structures where organic base resins are combined with inorganic particles (such as silicon oxide, tin oxide, titanium oxide, or zirconium oxide). This composite approach enables the window to simultaneously achieve flexibility for folding operations and sufficient hardness for mechanical durability.

Inventive Principle:

Principle #40Composite materials

2Reliability

If the window structure is optimized for folding characteristics, then excellent flexibility is achieved, but surface hardness deteriorates

Engineering Contradiction:

Improvefolding characteristicsVSAvoidsurface hardness

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

Different layers of the window structure have different local properties optimized for specific functions. The base layer and refractive layers are designed with higher flexibility to enable folding, while the hard coating layer is specifically engineered with higher hardness to provide surface protection and scratch resistance.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The combination of soft organic base resins with hard inorganic particles creates a composite structure where the organic components provide flexibility for folding while the inorganic particles contribute surface hardness and mechanical strength.

Inventive Principle:

Principle #40Composite materials

3Strength

If a thick window structure is used to improve mechanical properties, then surface hardness is enhanced, but folding characteristics deteriorate

Engineering Contradiction:

Improvesurface hardnessVSAvoidfolding characteristics

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

Instead of using a single thick layer, the window is segmented into multiple thin functional layers. This segmentation allows each layer to be optimized for its specific function while the overall structure maintains flexibility, as thin layers can better accommodate bending and folding stresses.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The window employs thin film structures that inherently provide flexibility. By using multiple thin layers rather than one thick layer, the window achieves sufficient surface hardness through the hard coating and inorganic particles while maintaining the flexibility needed for folding operations.

Inventive Principle:

Principle #30Flexible shells and thin films

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 window structure improves the display device's surface hardness and folding characteristics, ensuring enhanced mechanical properties and reliability during repeated folding operations.

Implementation Method 1

a window including a base layer disposed on the display panel, a hard coating layer disposed on the base layer, a high refractive layer disposed on the hard coating layer and including a first base resin, and a low refractive layer disposed on the high refractive layer and consisting of a first inorganic particle

Methodology Applied

Scientific EffectOptical interference: Interference

Implementation Method 2

forming a low refractive layer including a first inorganic particle on the high refractive layer using a physical deposition

Methodology Applied

Scientific EffectPhysical deposition: Deposition (physical)

Data Source

PatentUS20250321363A1Display device, electronic device and method of manufacturing the display device

Publication Date: 2025.10.16 SAMSUNG DISPLAY CO LTD

AI summary

A display device includes a display panel and a window disposed on the display panel. The window includes a base layer disposed on the display panel, a hard coating layer disposed on the base layer, a high refractive layer disposed on the hard coating layer and including a first base resin, and a low refractive layer disposed on the high refractive layer and consisting of a first inorganic particle.