Capacitive Data Carrier Modifiability via Conductive Structure Dynamics

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current capacitive data carriers are not suitable for documents as they are static and cannot be changed or modified, lacking flexibility and security features to protect valuable documents.

Innovation Solution

A system and method that allows for the generation of time-dependent signals on capacitive area sensors by modifying the electrically conductive structure on a device, enabling subsequent changes to the data carrier, such as applying or removing conductive material, which can be recognized by a surface sensor, allowing for manual or handwritten modifications.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a static electrically conductive structure is used on a capacitive data carrier, then the data carrier can be read by capacitive area sensors, but the data carrier cannot be modified or changed subsequently

Engineering Contradiction:
Improvemodifiability of data carrierVSAvoidstatic nature of conductive structure
Core Design Contradiction:
Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The patent applies the dynamics principle by transforming the static conductive structure into a dynamic one that can change its state. The conductive structure is designed to be modifiable through manual or automated processes, allowing it to transition between different conductive patterns. This enables the data carrier to be rewritten or updated by changing the physical configuration of the conductive elements, thereby achieving adaptability while maintaining detectability by capacitive sensors.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent employs parameter changes by modifying the electrical conductivity parameters of the data carrier surface. By changing the conductive properties (such as conductivity distribution, resistance patterns, or capacitive coupling characteristics) through manual marking, printing, or automated modification, the data carrier can represent different information states. This allows the same physical substrate to store multiple possible data configurations.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If RFID tags are used for self-identification, then copy-proof and counterfeit-proof identification is achieved, but the cost is too high for mass-market applications

Engineering Contradiction:
Improvecounterfeit protectionVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent applies this principle by using inexpensive capacitive data carrier substrates (such as paper, plastic, or thin film) that can be mass-produced at low cost. Instead of using expensive RFID chips, the invention uses simple conductive structures that can be applied to cheap materials through printing or coating techniques. The data carrier itself can be discarded or replaced economically, while the information stored on it provides the security function.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent replaces the electronic/magnetic field-based RFID system with a capacitive sensing system that operates on simpler electrical principles. By substituting the complex RFID transceiver electronics with passive capacitive structures and sensor arrays, the system achieves similar identification functionality at a fraction of the cost, making it suitable for mass-market applications.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Ease of manufacture

If optical codes are used for identification, then low cost and ease of manufacture are achieved, but the codes are easy to copy and lack tamper protection

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidtamper protection
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent applies local quality by creating non-uniform, position-specific conductive patterns on the data carrier. Each location on the carrier has a unique conductive configuration that contributes to the overall identification signal. This spatial variation in conductive properties makes the code harder to replicate than uniform optical barcodes, as the precise physical arrangement of conductive elements must be reproduced accurately.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent uses composite structures combining conductive materials with non-conductive substrates. The conductive layer (which could be metallic ink, conductive polymer, or other conductive coating) is applied to or integrated with the base material to create a multi-layer structure. This composite approach provides both the optical properties needed for printing/manufacturing and the electrical properties needed for capacitive sensing and tamper detection.

Inventive Principle:
Principle #40Composite materials

4Measurement precision

If a fixed electrically conductive structure is used, then consistent signal recognition is achieved, but the structure cannot be subsequently changed or adapted

Engineering Contradiction:
Improvesignal recognition accuracyVSAvoidsignal variability
Core Design Contradiction:
Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The patent applies preliminary action by pre-configuring the conductive structure in a default or initial state that provides a known reference signal for accurate recognition. This initial configuration ensures reliable baseline detection. The structure is designed to maintain this reference state while allowing controlled modifications afterward, enabling both accurate initial recognition and subsequent adaptability through structured changes to the conductive pattern.

Inventive Principle:
Principle #10Preliminary action

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

Enables flexible and secure data carriers that can be modified and read by capacitive area sensors, providing enhanced protection against forgery and manipulation, suitable for documents, and compatible with modern smartphones and tablets.

Implementation Method 1

capacitive area sensor configured to detect changes in a time-dependent signal on the sensor surface

Methodology Applied
Scientific EffectCapacitance: Capacitance

Implementation Method 2

electrically conductive base structure, wherein a subsequent modification of the electrically conductive base structure is realized

Methodology Applied
Scientific EffectElectrical Conductivity: Conduction (electrical)

Data Source

PatentEP3577594B1Device and use of the device for generating a variable time-dependent signal on a capacitive surface sensor
Publication Date: 2023.08.09 PRISMADE LABS GMBH
  • EP3577594B1 patent drawingFigure 1a~1c
  • EP3577594B1 patent drawingFigure 2a~2b
  • EP3577594B1 patent drawingFigure 3a~3b

AI summary

The invention relates to a system and method for generating a variable time-dependent signal on a capacitive surface sensor, and to the use of a pen for changing an electrically conductive structure on a device.