Touch-Pen Sensor Layer With Differential Noise Filtering

Solution Overview

Problem

Existing touch-based input systems in multimedia electronic devices struggle to accurately sense inputs from pens due to noise interference.

Innovation Solution

The electronic device incorporates a sensor layer with electrode groups arranged in specific directions and a sensor driver that operates in a touch mode or a pen mode, utilizing differential amplifiers and coupling capacitors to differentiate between touch and pen inputs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a touch-based input system uses a sensor layer to sense pen input, then the system can detect pen touches, but noise interference prevents accurate sensing of the pen input

Engineering Contradiction:

Improvepen input sensing accuracyVSAvoidnoise interference

Core Design Contradiction:

Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The sensor layer is divided into multiple electrode groups arranged in different directions (first electrode groups in a first direction, second electrode groups in a second direction). Each electrode group contains division electrodes and cross electrodes that are spatially segmented to independently sense signals, allowing the system to differentiate pen input from noise through directional signal comparison

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different electrode groups are configured with specific local properties: first electrode groups are optimized for sensing in one direction while second electrode groups are optimized for the perpendicular direction. This local specialization allows each electrode group to contribute differently to the overall signal processing, enabling noise filtering while maintaining pen input detection accuracy

Inventive Principle:

Principle #3Local quality

2Measurement precision

If additional digitizers are added to improve pen input sensing, then sensing accuracy improves, but device thickness and weight increase

Engineering Contradiction:

Improvepen input detection accuracyVSAvoiddevice weight

Core Design Contradiction:

Measurement precisionVSWeight of moving object

Solution Approach 1:

The sensor layer serves multiple functions: it detects both touch input and pen input using the same electrode structure. By configuring electrode groups in different directions and using differential signal processing, the single sensor layer achieves both touch sensing and precise pen input detection without requiring separate digitizer layers

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent combines touch sensing and pen input sensing capabilities into a single integrated sensor layer. The first and second electrode groups work together within the same layer structure, merging multiple sensing functions into one component to avoid increasing device thickness and weight

Inventive Principle:

Principle #5Merging (Combining)

3Measurement precision

If additional digitizers are added to improve pen input sensing, then sensing accuracy improves, but device thickness increases

Engineering Contradiction:

Improvepen input detection accuracyVSAvoiddevice thickness

Core Design Contradiction:

Measurement precisionVSLength of stationary object

Solution Approach 1:

The sensor layer serves multiple functions: it detects both touch input and pen input using the same electrode structure. By configuring electrode groups in different directions and using differential signal processing, the single sensor layer achieves both touch sensing and precise pen input detection without requiring separate digitizer layers

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent combines touch sensing and pen input sensing capabilities into a single integrated sensor layer. The first and second electrode groups work together within the same layer structure, merging multiple sensing functions into one component to avoid increasing device thickness

Inventive Principle:

Principle #5Merging (Combining)

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

This configuration enhances the ability to accurately sense pen inputs while minimizing noise interference, allowing for precise input detection without the need for additional digitizers, thus maintaining device thickness and weight.

Implementation Method 1

A sensor layer of the touch-based input system may sense a touch or pressure of an object

Methodology Applied

Scientific EffectCapacitance: Capacitance

Implementation Method 2

the sensor driver may include a differential amplifier, and in the second mode, an inverting terminal of the differential amplifier may be electrically connected to the first sensing electrode, and a non-inverting terminal of the differential amplifier may be electrically connected to the second sensing electrode

Methodology Applied

Scientific EffectElectromagnetic Induction: Electromagnetic Induction

Data Source

PatentUS20250251827A1Electronic device

Publication Date: 2025.08.07 SAMSUNG DISPLAY CO LTD

AI summary

An electronic device includes a sensor layer and a sensor driver configured to drive the sensor layer and operate in one of a first mode for sensing a touch input and a second mode for sensing a pen input. The sensor layer includes a plurality of first electrode groups arranged along a first direction and a plurality of second electrode groups arranged along a second direction crossing the first direction and each including a first sensing electrode and a second sensing electrode. A plurality of coupling capacitors are between the first sensing electrode and the second sensing electrode.