Flexible Display Panel with Segmented Inorganic Control Layer

Solution Overview

Problem

Flexible display panels with inorganic pixel control array layers are prone to cracking and peeling due to repeated bending stresses, limiting their durability and functionality.

Innovation Solution

The implementation of a flexible display panel design that separates the inorganic pixel control array layer from the bendable region by placing an organic flexible layer instead, with pixel units connected to thin film transistors on unbendable regions via extended signal wires, and optionally using island-shaped pixel control array units with flexible layers between them to distribute stress.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an inorganic pixel control array layer is used to control pixel light emission, then the display panel achieves proper pixel control functionality, but the inorganic film layer cracks and peels under repeated bending stresses

Engineering Contradiction:

Improvepixel control functionalityVSAvoidresistance to bending stress

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The display panel is divided into a bendable region and an unbendable region. The inorganic pixel control array layer is placed only in the unbendable region, while the bendable region contains only the flexible substrate and pixel electrodes. This segmentation allows the inorganic layer to remain in the rigid portion where it provides reliable pixel control without experiencing bending stresses.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The inorganic pixel control array layer is extracted from the bendable region and placed exclusively in the unbendable region. This extraction removes the source of the problem (the brittle inorganic layer) from the area subject to bending stress, while preserving its essential function in controlling pixel light emission through extended signal wires that reach into the bendable region.

Inventive Principle:

Principle #2Taking out (Extraction)

2Ease of operation

If the inorganic pixel control array layer is placed in the bendable region to enable pixel control, then the display can be controlled properly, but the inorganic film layer is damaged by repeated bending stresses

Engineering Contradiction:

Improvepixel controlVSAvoiddurability under bending

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The display panel is divided into a bendable region and an unbendable region. The inorganic pixel control array layer is placed only in the unbendable region, while the bendable region contains only the flexible substrate and pixel electrodes. This segmentation allows the inorganic layer to remain in the rigid portion where it provides reliable pixel control without experiencing bending stresses.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Extended signal wires act as intermediaries, connecting the inorganic pixel control array layer in the unbendable region to the pixel electrodes in the bendable region. These flexible signal wires transmit control signals and power from the rigid control layer to the flexible display region, enabling pixel control functionality without requiring the brittle inorganic layer to be present in the bendable region.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Ease of operation

If the inorganic pixel control array layer is used for pixel control, then proper display control is achieved, but cracking expands to influence other regions under repeated stress

Engineering Contradiction:

Improvedisplay controlVSAvoidcrack propagation

Core Design Contradiction:

Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The display panel is divided into a bendable region and an unbendable region. The inorganic pixel control array layer is placed only in the unbendable region, while the bendable region contains only the flexible substrate and pixel electrodes. This segmentation allows the inorganic layer to remain in the rigid portion where it provides reliable pixel control without experiencing bending stresses.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The inorganic pixel control array layer is extracted from the bendable region and placed exclusively in the unbendable region. This extraction removes the source of the problem (the brittle inorganic layer) from the area subject to bending stress, while preserving its essential function in controlling pixel light emission through extended signal wires that reach into the bendable region.

Inventive Principle:

Principle #2Taking out (Extraction)

Data Source

PatentUS11217645B2Flexible display panel having a pixel unit corresponding to a bendable area electrically connected to a portion of a first thin film transistor corresponding to an unbendable region

Publication Date: 2022.01.04 WUHAN CHINA STAR OPTOELECTRONICS SEMICONDUCTOR DISPLAY TECHNOLOGY CO LTD

AI summary

A flexible display panel is provided, comprising: a substrate provided with a bendable region and an unbendable region; a pixel control array layer corresponding to the unbendable region; a flexible layer corresponding to the bendable region; and a pixel unit; the pixel unit corresponding to the bendable region is connected to the first thin film transistor in the pixel control array layer; alternatively, a pixel control array unit is provided at intervals in the flexible layer, the pixel unit corresponding to the bendable region is connected to the second thin film transistor in the pixel control array unit.