Touch Sensor Electrode Segmentation for Ghost Touch Suppression

Solution Overview

Problem

Touch sensors in display panels experience issues with cathode re-transmission phenomena due to rapid external temperature changes, leading to ghost touches and noise interference, particularly in larger screens.

Innovation Solution

A touch sensor design with multiple reception electrodes, including first and second patterns, where the sensing unit cancels noise signals by subtracting signals from adjacent electrodes, improving sensitivity and reducing noise.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a touch sensor is implemented with a single layer or double layer structure, then the device complexity is reduced, but ghost touches and noise signals occur due to cathode re-transmission phenomena

Engineering Contradiction:

Improvetouch sensor structureVSAvoidtouch detection accuracy

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The reception electrode is divided into multiple reception electrode patterns (first pattern and second pattern) arranged in different regions. This segmentation allows the system to capture different signal components, including the cathode re-transmission noise, which can then be separated and eliminated through differential processing, thereby improving touch detection accuracy without significantly increasing overall device complexity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces an intermediate signal processing mechanism where the sensing unit calculates a differential signal between multiple reception electrode patterns. This intermediary processing step acts as a mediator that isolates and removes the cathode re-transmission noise component, allowing the true touch signal to be extracted accurately.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If multiple reception electrode patterns are used to cancel noise signals, then touch sensing accuracy is improved, but the device complexity increases

Engineering Contradiction:

Improvetouch sensing accuracyVSAvoidtouch sensor structure

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The reception electrode is divided into multiple reception electrode patterns (first pattern and second pattern) arranged in different regions. This segmentation allows the system to capture different signal components, including the cathode re-transmission noise, which can then be separated and eliminated through differential processing, thereby improving touch detection accuracy without significantly increasing overall device complexity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent combines multiple reception electrode patterns into a unified reception electrode structure that shares common connections and control circuits. This merging approach allows the system to achieve noise cancellation functionality while minimizing the increase in device complexity by reusing existing structural elements and control logic.

Inventive Principle:

Principle #5Merging (Combining)

3Illumination intensity

If the OLED panel resolution is increased to FHD, then the display quality is improved, but the cathode re-transmission phenomenon becomes more pronounced

Engineering Contradiction:

Improvedisplay resolutionVSAvoidcathode re-transmission noise

Core Design Contradiction:

Illumination intensityVSObject-generated harmful factors

Solution Approach 1:

The reception electrode is divided into multiple reception electrode patterns (first pattern and second pattern) arranged in different regions. This segmentation allows the system to capture different signal components, including the cathode re-transmission noise, which can then be separated and eliminated through differential processing, thereby improving touch detection accuracy without significantly increasing overall device complexity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent converts the harmful cathode re-transmission noise into a useful signal component by using it as a reference in the differential calculation. The noise signal captured by the reception electrode patterns is transformed from a detrimental factor into a beneficial reference that enables accurate noise cancellation and enhances overall touch sensing performance.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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 touch sensing accuracy by minimizing ghost touches and noise, especially in environments with rapid temperature fluctuations, by effectively canceling cathode re-transmission and other noise signals.

Implementation Method 1

the touch sensor includes a plurality of driving electrodes and a plurality of reception electrodes... sense a touch position of an object to be touched

Methodology Applied

Scientific EffectCapacitance: Capacitance

Implementation Method 2

the sensing unit cancels a noise signal caused by a cathode retransmission phenomenon of the ELVSS layer contained in each of a first sensing signal and a second sensing signal by subtracting the second sensing signal outputted through the second reception electrode patterns from the first sensing signal outputted through the first reception electrode patterns

Methodology Applied

Scientific EffectSignal subtraction:

Data Source

PatentUS12493384B2Touch sensor and touch input device comprising same

Publication Date: 2025.12.09 HIDEEP INC

AI summary

A touch input device according to an embodiment of the present invention includes: a display panel including an ELVSS layer; a touch sensor disposed on the ELVSS layer of the display panel; and a sensing unit electrically connected with the touch sensor to sense a touch position of an object to be touched.