Integrated Touch Display Electrodes with Beacon-Based Pen Recognition

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing touch display devices face challenges in efficiently supporting both finger touch and pen touch inputs, with existing technologies struggling to accurately detect and differentiate between the two, leading to difficulties in providing seamless user interaction.

Innovation Solution

A touch display device with embedded touch electrodes that employs a Long Horizontal Blank (LHB) driving method, alternating display and touch periods, and a beacon signal system to distinguish between finger and pen inputs, enabling multi-pen recognition and sensing of pen pressures, tilts, and additional data through synchronized signal communication.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a capacitance touch method is used to detect finger touches, then touch detection capability is improved, but the ability to accurately distinguish and process pen touches deteriorates

Engineering Contradiction:
Improvetouch detection capabilityVSAvoidpen touch recognition accuracy
Core Design Contradiction:
Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The patent segments the touch detection process into distinct phases: finger touch detection using capacitance changes and pen touch detection using electromagnetic induction. By separating these detection mechanisms into different operational modes, the system can optimize each for its specific purpose without interference, thereby improving both finger touch detection accuracy and pen touch recognition capability

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces an intermediary detection mechanism (electromagnetic induction sensing) that specifically targets pen inputs. This intermediary system works alongside the primary capacitance-based finger detection, allowing the display to differentiate between finger and pen touches by detecting the electromagnetic signals emitted by active pens, thus resolving the contradiction between general touch detection and specific pen recognition

Inventive Principle:
Principle #24Intermediary (Mediator)

2Volume of moving object

If touch electrodes are embedded in the display panel to reduce size, then device compactness is improved, but the complexity of manufacturing and integrating multiple functions deteriorates

Engineering Contradiction:
Improvedevice sizeVSAvoidmanufacturing complexity
Core Design Contradiction:
Volume of moving objectVSDevice complexity

Solution Approach 1:

The patent implements multi-functionality by designing the embedded touch electrodes to serve dual purposes: capacitance-based finger touch detection and electromagnetic induction-based pen detection. This universal design allows the same physical structure to support multiple input methods, reducing the need for separate dedicated components and thereby simplifying manufacturing while maintaining compact form factor

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

Solution Approach 2:

The patent merges the display function and touch sensing function into a single integrated structure. By combining the display panel and touch electrodes into one unit, the system eliminates the need for separate touch screen layers, reducing overall device size and simplifying the manufacturing process while enabling both finger and pen input capabilities through the integrated structure

Inventive Principle:
Principle #5Merging (Combining)

3Ease of operation

If the display operates continuously to provide seamless user interaction, then user experience is improved, but power consumption increases

Engineering Contradiction:
Improveuser interaction seamlessnessVSAvoidpower consumption
Core Design Contradiction:
Ease of operationVSUse of energy by moving object

Solution Approach 1:

The patent employs periodic action by implementing discontinuous transmission intervals for the display, where the display operates in active periods to provide seamless user interaction and enters sleep periods to conserve power. During sleep periods, the display can still detect touches through the embedded electrodes, maintaining responsiveness while significantly reducing power consumption, thus resolving the contradiction between seamless interaction and energy efficiency

Inventive Principle:
Principle #19Periodic 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

The solution allows for efficient and accurate detection of both finger and pen touches, supporting multi-pen interactions with reduced power consumption and improved user experience by enhancing the recognition and processing of pen-related data.

Implementation Method 1

a capacitance touch method that detects the presence or absence of a touch, touch coordinates, and the like, based on a capacitance between touch electrodes or a change in capacitance between a touch electrode and a pointer

Methodology Applied
Scientific EffectCapacitance: Capacitance

Implementation Method 2

an electromagnetic induction touch method

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP4024181B1Touch display device, active pen, touch system, touch circuit, and pen recognition method
Publication Date: 2025.07.02 LG DISPLAY CO LTD
  • EP4024181B1 patent drawingFigure 1
  • EP4024181B1 patent drawingFigure 2
  • EP4024181B1 patent drawingFigure 3

AI summary

Embodiments described herein provide a touch display device, an active pen, a touch system, a touch circuit, and a pen recognition method capable of efficiently providing a display function, a touch-sensing function, and a pen-touch-sensing function.