Multilayer Sensing Structure With Reduced Electrical Distance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing multilayer structures for sensing applications face challenges such as large electrodes taking up space, increased costs, assembly complexity, and sensitivity issues due to separate components, which complicate manufacturability and lead to loose components during injection molding.

Innovation Solution

A multilayer structure with a molded or cast plastic layer of electrically insulating material, featuring a first and second film layer with reactance sensing electronics, where the electrical distance between the film layer and sensing element is reduced by a physical feature like a recess or conductive element molded into the plastic layer, improving sensing sensitivity while maintaining a long electrical connection to the control circuitry.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If large electrodes are arranged on the surface or close to the surface of the device, then sensing capability is achieved, but device area is reduced and assembly complexity increases

Engineering Contradiction:
Improvesensing capabilityVSAvoiddevice area
Core Design Contradiction:
Measurement precisionVSArea of stationary object

Solution Approach 1:

The patent transitions from planar 2D electrode arrangements on the surface to a 3D vertical configuration where electrodes are embedded within multilayer structures. This dimensional change allows sensing functionality to be achieved without occupying additional surface area, as electrodes are positioned at different depths and layers rather than spreading out on the surface.

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

Solution Approach 2:

The patent implements nested electrode structures where multiple electrodes are positioned within nested layers of the device. Inner electrodes are surrounded by outer electrodes at different depths, creating a compact nested arrangement that provides comprehensive sensing coverage while minimizing the overall device footprint.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Measurement precision

If separate components are used for sensing elements and control circuitry, then sensing functionality is achieved, but manufacturing cost and assembly time increase

Engineering Contradiction:
Improvesensing functionalityVSAvoidassembly time
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The patent merges sensing elements, control circuitry, and electrode structures into a single integrated multilayer component. The control circuitry is embedded within the same layered structure as the sensing electrodes, eliminating the need for separate components and reducing assembly steps to a single manufacturing process.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The multilayer structure serves multiple functions simultaneously: it provides mechanical support, electrical insulation, sensing capability, and signal processing. Each layer is designed to perform multiple roles, such as providing both structural integrity and electrical isolation, thereby reducing the total number of components needed.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Measurement precision

If separate components are used for sensing elements and control circuitry, then sensing functionality is achieved, but device complexity and manufacturability worsen

Engineering Contradiction:
Improvesensing functionalityVSAvoidstructure complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the sensing device into distinct functional layers, each with a specific role. This segmentation into manageable layers simplifies the manufacturing process by allowing each layer to be fabricated and positioned independently, then integrated into the final structure through a standardized multilayer assembly process.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent combines multiple functional elements into an integrated multilayer structure where sensing electrodes, control circuitry, insulation layers, and support structures are merged into a single cohesive component. This integration reduces the number of separate parts and simplifies manufacturing while maintaining sensing functionality.

Inventive Principle:
Principle #5Merging (Combining)

4Ease of manufacture

If components are subject to pressures in injection molding process, then manufacturing is achieved, but components become loose and reliability decreases

Engineering Contradiction:
Improvemanufacturing capabilityVSAvoidcomponent stability
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent employs composite multilayer materials with varying mechanical and electrical properties optimized for injection molding. The composite structure includes layers with different durometers and thermal expansion coefficients that work together to absorb molding pressures while maintaining component stability and preventing loosening during the manufacturing process.

Inventive Principle:
Principle #40Composite materials

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

Enhances sensing sensitivity by reducing the electrical distance between the sensing element and area, while maintaining a sufficient connection distance to reduce interference, thus improving the performance and manufacturability of touch, proximity, and force sensing applications.

Implementation Method 1

reactance sensing electronics for reactance, such as (projected) capacitance or inductance, sensing of one or more selected target quantities and/or qualities

Methodology Applied
Scientific EffectCapacitance: Capacitance

Implementation Method 2

reactance sensing electronics for reactance, such as (projected) capacitance or inductance, sensing of one or more selected target quantities and/or qualities

Methodology Applied
Scientific EffectInductance: Inductor

Implementation Method 3

the electrical distance between the film layer on the second side of said plastic layer and the sensing element is locally reduced by at least one physical feature at the position of the sensing area of the second film layer to improve the associated sensing sensitivity

Methodology Applied
Scientific EffectElectrical distance reduction:

Data Source

PatentEP3844877B1Integrated multilayer structure for use in sensing applications and method for manufacturing thereof
Publication Date: 2023.10.18 TACTOTEK
  • EP3844877B1 patent drawingFigure 1A~1B
  • EP3844877B1 patent drawingFigure 2A~2B
  • EP3844877B1 patent drawingFigure 3A~3B

AI summary

An integrated multilayer structure for use in sensing applications and a method of manufacture are presented. The multilayer structure comprises at least one molded or cast plastic layer and a film layer on both first and second sides of said plastic layer. The film layer on the first side of said plastic layer is provided with reactance sensing electronics. The sensing electronics comprises at least one sensing element and an electrical connection for connecting the sensing element to an associated control circuitry. The film layer on the second side of said plastic layer having a sensing area superimposed with the sensing element of the sensing electronics. The electrical distance between the film layer on the second side of said plastic layer and the sensing element being locally reduced by a physical feature at the position of the sensing area of the film layer to improve the associated sensing sensitivity.