Flexible Wiring Substrate with Flared Extension for LCD Panel Attachment

Solution Overview

Problem

Liquid crystal display devices face issues with the flexible printed circuit (FPC) substrate bending, leading to potential detachment of the liquid crystal panel from the frame due to elastic restoring forces, and the panel substrate's strength is compromised, making it prone to breakage under external forces.

Innovation Solution

The design incorporates a flexible wiring substrate with a wide width portion connected to a flaring extension portion of the substrate, where the edge of the wide width portion is matched to the edge of the extension portion, reducing the bending stress and enhancing mechanical strength by using an adhesive agent, and optimizing the shape and dimensions of the substrate to prevent breakage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the FPC substrate is bent to connect to the liquid crystal panel, then the liquid crystal panel can be electrically connected to external devices, but the elastic restoring force causes the liquid crystal panel to detach and float from the frame

Engineering Contradiction:

Improveelectrical connectionVSAvoidpanel attachment stability

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The patent applies local quality by creating a reinforcement structure specifically at the extension portion of the substrate where it connects to the FPC substrate. This reinforcement portion is formed by extending the substrate width at the connection area, providing localized structural support exactly where the bending stress occurs, without making the entire substrate thicker or more complex.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent segments the substrate into distinct functional portions: a main panel area and an extension portion with increased width. This segmentation allows the extension portion to specifically handle the mechanical stress from FPC connection while the main panel maintains its original thin profile for display functionality.

Inventive Principle:

Principle #1Segmentation

2Volume of moving object

If the panel substrate is narrowed to achieve a low-profile shape, then the device thickness is reduced, but the substrate strength is weakened making it prone to breakage

Engineering Contradiction:

Improvedevice thicknessVSAvoidsubstrate mechanical strength

Core Design Contradiction:

Volume of moving objectVSStrength

Solution Approach 1:

The patent applies local quality by creating a reinforcement structure specifically at the extension portion of the substrate where it connects to the FPC substrate. This reinforcement portion is formed by extending the substrate width at the connection area, providing localized structural support exactly where the bending stress occurs, without making the entire substrate thicker or more complex.

Inventive Principle:

Principle #3Local quality

3Area of stationary object

If the FPC substrate width is increased to match the panel width, then the connection area is enlarged, but the elastic restoring force becomes larger causing greater detachment risk

Engineering Contradiction:

Improveconnection areaVSAvoidelastic restoring force

Core Design Contradiction:

Area of stationary objectVSForce

Solution Approach 1:

The patent applies local quality by creating a reinforcement structure specifically at the extension portion of the substrate where it connects to the FPC substrate. This reinforcement portion is formed by extending the substrate width at the connection area, providing localized structural support exactly where the bending stress occurs, without making the entire substrate thicker or more complex.

Inventive Principle:

Principle #3Local quality

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 effectively prevents the liquid crystal panel from detaching from the frame and enhances the mechanical strength of the substrate, reducing the risk of breakage due to external forces like impact or vibration.

Implementation Method 1

The FPC substrate is connected to the extension portion by using an adhesive agent

Methodology Applied

Scientific EffectAdhesion: Adhesive

Implementation Method 2

In the state where the FPC substrate is bent in such a manner, a force to return the FPC substrate to the original shape is generated inside the FPC substrate by the elasticity of the FPC substrate itself

Methodology Applied

Scientific EffectElasticity: Elasticity

Data Source

PatentUS7710528B2Electro optical device and electronic apparatus

Publication Date: 2010.05.04 MAGNOLIA WHITE CORP

AI summary

There is provided an electro optical device including an electro optical panel formed by sticking a first substrate and a second substrate together, and a flexible wiring substrate connected to the electro optical panel. The first substrate includes a extension portion flaring from the second substrate, the wiring substrate includes a base material having flexibility and a conductive pattern provided on the base material, the wiring substrate is connected to the extension portion of the first substrate by using an adhesive agent, the wiring substrate includes a wide width portion connected to the extension portion and a narrow width portion continuing to the wide width portion and extending outwardly from an edge side of the extension portion in the flaring direction, and an edge side of the wide width portion at the narrow width portion side is matched to the position of the edge side of the extension portion in the flaring direction or is positioned inside of the edge side of the extension portion in the flaring direction.