Flexible Display Panel Non-Display Area Thinning

Solution Overview

Problem

Flexible display panels face stress concentration and breakage issues when bent due to the presence of organic layers and metal wires in the non-display area, leading to electrical signal disruptions.

Innovation Solution

A flexible display panel structure with a thinner non-display area and a thicker display area, featuring a first organic sub-layer, intermediate layer, and bonding sub-layer in the display area, and a second organic sub-layer in both areas, along with a thin film transistor layer and encapsulation layer, where the bonding sub-layer is made of a silane coupling agent and the non-display area is converted into a single-layer organic structure through irradiation and mechanical separation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a two-layer organic structure is used in the non-display area to ensure reliability, then the reliability is improved, but the bending resistance deteriorates due to stress concentration

Engineering Contradiction:
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent applies different organic layer structures to different areas: the display area maintains a two-layer structure (first organic sub-layer + second organic sub-layer) for reliability, while the non-display area uses only the second organic sub-layer to reduce thickness and stress concentration. This local differentiation resolves the contradiction between reliability and bending resistance.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent segments the flexible substrate into display area and non-display area, applying different structural configurations to each segment. The non-display area is separated from the full two-layer structure, allowing independent optimization for bending performance without compromising the display area's reliability.

Inventive Principle:
Principle #1Segmentation

2Reliability

If multiple organic layers and metal wires are present in the non-display area, then the reliability is improved, but the bending radius reduction causes large stress concentration leading to cracks and breaks

Engineering Contradiction:
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent extracts the first organic sub-layer from the non-display area, removing the source of excessive stress concentration. Only the second organic sub-layer remains in the non-display area, significantly reducing the amount of material that generates stress during bending while preserving the essential protective and functional properties.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent implements local quality by making the non-display area structurally different from the display area. The non-display area has reduced organic layer thickness specifically to minimize stress concentration during bending, while the display area maintains the full two-layer structure for reliability.

Inventive Principle:
Principle #3Local quality

3Reliability

If the non-display area maintains the same thickness as the display area, then the reliability is improved, but the flexibility and bending performance deteriorate

Engineering Contradiction:
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent applies local quality by creating thickness variation across the substrate: the display area maintains greater thickness for reliability, while the non-display area has reduced thickness (only second organic sub-layer) to enhance flexibility and bending performance. This resolves the contradiction between reliability and flexibility.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent creates a dynamic thickness profile that adapts to functional requirements: thicker in the display area for stability and reliability, thinner in the non-display area for flexibility. This dynamic structural variation allows the substrate to bend more easily without compromising the reliability of the active display region.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentUS11264579B2Flexible display panel and preparation method thereof
Publication Date: 2022.03.01
  • US11264579B2 patent drawing
  • US11264579B2 patent drawing
  • US11264579B2 patent drawing

AI summary

In a flexible display panel and a preparation method thereof provided by the present application, the flexible display panel includes a flexible substrate including a display area and a non-display area connected to each other, a thickness of the flexible substrate in the non-display area is less than a thickness of the flexible substrate in the display area; a thin film transistor layer disposed on one side of the flexible substrate; and an organic light-emitting layer disposed on one side of the thin film transistor layer away from the flexible substrate.