Capacitive Touch FPC Parallel Circuit Layout for Compact Substrate Use

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing flexible circuit boards (FPCs) in capacitive touchscreens occupy a large space, leading to inefficient substrate utilization and increased costs due to their perpendicular arrangement, which hinders compact design and results in substrate wastage.

Innovation Solution

The FPCs are redesigned with sensing and driving circuits arranged in parallel or on the same line, allowing for bending and perpendicular alignment, with a bending area near the IC driving chip and contacts positioned outside the bending area, enabling compact substrate arrangement and efficient lamination.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If the sensing circuit and driving circuit are arranged perpendicularly on the FPC substrate, then the circuits can be connected to the touchscreen panel, but the FPC occupies a large space and substrate utilization is low

Engineering Contradiction:
Improvesubstrate utilization areaVSAvoidcircuit arrangement complexity
Core Design Contradiction:
Area of stationary objectVSDevice complexity

Solution Approach 1:

The patent transitions from a two-dimensional perpendicular arrangement to a one-dimensional linear arrangement of circuits along the same line. The sensing circuit and driving circuit are positioned sequentially along the length of the FPC substrate rather than occupying perpendicular planes, thereby reducing the area footprint while maintaining all necessary connections to the touchscreen panel.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

Instead of arranging circuits perpendicular to each other as in conventional designs, the patent inverts the arrangement strategy by placing the sensing circuit and driving circuit in parallel along the same line. This inversion of the traditional spatial relationship between circuits achieves compactness without compromising functionality.

Inventive Principle:
Principle #13The other way round (Inversion)

2Productivity

If the sensing circuit and driving circuit are arranged perpendicularly, then connections can be established, but the arrangement is not compact and increases cost

Engineering Contradiction:
Improvesubstrate utilization rateVSAvoidmanufacturing cost
Core Design Contradiction:
ProductivityVSEase of manufacture

Solution Approach 1:

The patent merges the spatial occupation of the sensing circuit and driving circuit into a single linear pathway along the FPC substrate. By combining their arrangements along the same line rather than separating them in perpendicular directions, the design achieves compactness that increases substrate utilization rate and reduces manufacturing costs through more efficient material usage.

Inventive Principle:
Principle #5Merging (Combining)

3Reliability

If the FPC is designed with perpendicular circuit arrangement, then circuit functionality is maintained, but compact integration is hindered

Engineering Contradiction:
Improvecircuit connection reliabilityVSAvoidFPC space occupation
Core Design Contradiction:
ReliabilityVSVolume of moving object

Solution Approach 1:

The patent segments the FPC design into distinct functional zones along a linear arrangement: the sensing circuit region, the bending area, and the driving circuit region. This segmentation allows each component to maintain its functionality while being positioned sequentially along the substrate, ensuring reliable connections to the touchscreen panel while minimizing overall space occupation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent incorporates a bending area positioned between the sensing circuit and driving circuit, which is pre-designed to accommodate the necessary flexibility and connection requirements. This preliminary arrangement of the bending zone ensures that the circuits can be reliably connected to the panel while the overall FPC maintains a compact linear profile.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3089000B1FPC of capacitive touch screen and method for mounting FPC
Publication Date: 2021.02.03 KUNSHAN VISIONOX DISPLAY TECH
  • EP3089000B1 patent drawingFigure 1~2
  • EP3089000B1 patent drawingFigure 3
  • EP3089000B1 patent drawingFigure 4

AI summary

An FPC of a capacitive touchscreen and a method for mounting the FPC. The FPC comprises a sensing circuit and a driving circuit which respectively matches with a sensing circuit layer and a driving circuit layer of a capacitive touchscreen panel and have several contacts for matching the sensing circuit layer and the driving circuit layer for corresponding connection; an IC driving chip, disposed between the sensing circuit and the driving circuit. The sensing circuit and the driving circuit are disposed in parallel or on the same line. The sensing circuit or the driving circuit is provided with a bending area, and the sensing circuit or the driving circuit is able to be turned towards the driving circuit or the sensing circuit, so as to allow the sensing circuit to match the sensing circuit layer and allow the driving circuit to match the driving circuit layer. According to the present invention, the FPCs of the capacitive touchscreen can be compactly arranged on a substrate, so that the utilization rate of the substrate is greatly increased and the cost is reduced.