Flexible Display Circuit Board Bending Structure for Signal Reliability

Solution Overview

Problem

Flexible circuit boards in silicon-based OLED display devices are prone to damage and signal transmission issues due to bending, leading to reduced service life and poor performance.

Innovation Solution

The flexible circuit board is designed with a bent region featuring openings or grooves along the bending axis, with traces that do not overlap the openings, allowing stress relief and improved signal transmission.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of stationary object

If the flexible circuit board is bent to match the structure of the whole machine and minimize volume, then the display module volume is reduced, but the bent area of the flexible circuit board is prone to damage

Engineering Contradiction:

Improvedisplay module volumeVSAvoidservice life of flexible circuit board

Core Design Contradiction:

Volume of stationary objectVSReliability

Solution Approach 1:

The flexible circuit board is divided into distinct regions: a bent region and non-bent regions. The bent region is further segmented with multiple openings (through holes or grooves) along the bending axis, creating discrete segments that can independently manage stress during bending, preventing damage while maintaining compact form factor.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The bent region of the flexible circuit board is designed with a porous structure through the inclusion of multiple openings (through holes or grooves). This porous design allows the material to flex more easily during bending while maintaining structural integrity, reducing stress concentration and preventing damage to the circuit board.

Inventive Principle:

Principle #31Porous materials

2Volume of stationary object

If the flexible circuit board is bent to minimize display module volume, then compactness is improved, but signal transmission quality deteriorates

Engineering Contradiction:

Improvedisplay module volumeVSAvoidsignal transmission quality

Core Design Contradiction:

Volume of stationary objectVSReliability

Solution Approach 1:

The flexible circuit board is divided into distinct regions: a bent region and non-bent regions. The bent region is further segmented with multiple openings (through holes or grooves) along the bending axis, creating discrete segments that can independently manage stress during bending, preventing damage while maintaining compact form factor.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the flexible circuit board are designed with different properties: the bent region contains openings and traces arranged to handle mechanical stress, while the non-bent regions maintain standard circuit board structure for optimal signal transmission. The wiring layer traces in the bent region are specifically configured to avoid overlapping openings, ensuring signal integrity is maintained even in the flexed area.

Inventive Principle:

Principle #3Local quality

3Reliability

If openings are added to the bent region to relieve stress, then service life is improved, but device complexity increases

Engineering Contradiction:

Improveservice life of flexible circuit boardVSAvoidstructure complexity of flexible circuit board

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The flexible circuit board is divided into distinct regions: a bent region and non-bent regions. The bent region is further segmented with multiple openings (through holes or grooves) along the bending axis, creating discrete segments that can independently manage stress during bending, preventing damage while maintaining compact form factor.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The flexible circuit board utilizes a thin-film structure that can be easily formed with openings through standard manufacturing processes. The flexible nature of the thin film allows it to accommodate the openings while maintaining the necessary mechanical properties for bending and signal transmission, without requiring complex reinforcement structures.

Inventive Principle:

Principle #30Flexible shells and thin films

Data Source

PatentUS12532621B2Display module and display device

Publication Date: 2026.01.20 KUNMING BOE DISPLAY TECH CO LTD

AI summary

A display module includes a display substrate and a flexible circuit board bonding-connected with the display substrate, wherein the flexible circuit board is bent to a side of the display substrate away from a display side; the flexible circuit board includes a bent region and non-bent regions located at both sides of the bent region; the bent region includes a bending axis, the flexible circuit board is bent along the bending axis, the bent region is provided with one or more openings at a position of the bending axis, and the openings are through holes penetrating the flexible circuit board or grooves not penetrating the flexible circuit board; the bent region includes at least one wiring layer, the wiring layer of the bent region includes multiple traces extending to the non-bent regions on both sides of the bent region, and the plurality of traces do not overlap with the openings.