Fringe-Field Capacitive Sensor Layout for Compact Air Gesture Detection

Solution Overview

Problem

Conventional gesture recognition systems require large space and high energy consumption due to the need for complex sensors and processing circuits, making them inefficient for detecting air gestures.

Innovation Solution

A capacitive sensor with M plate pairs, where each pair consists of a first and second plate with a plate length to spacing ratio between 1 and 30, utilizing a fringe field effect to detect air gestures with low energy consumption and small size, allowing for efficient detection of air gestures in electronic devices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If millimeter wave radar sensor is used for gesture recognition, then gesture detection capability is improved, but device size and energy consumption increase significantly

Engineering Contradiction:

Improvegesture detection capabilityVSAvoiddevice size

Core Design Contradiction:

Measurement precisionVSVolume of stationary object

Solution Approach 1:

The patent extracts only the essential capacitive sensing function from complex radar systems, using simple plate pairs to detect gestures through capacitance changes caused by hand proximity, eliminating the need for bulky radar sensors while maintaining gesture detection capability

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the detection parameter from electromagnetic wave reflection (radar) to capacitance variation (capacitive sensing), enabling gesture recognition with much smaller components that have lower power consumption and smaller form factor

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If millimeter wave radar sensor is used for gesture recognition, then gesture detection capability is improved, but energy consumption increases

Engineering Contradiction:

Improvegesture detection capabilityVSAvoidenergy consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by stationary object

Solution Approach 1:

The patent extracts only the essential capacitive sensing function from complex radar systems, using simple plate pairs to detect gestures through capacitance changes caused by hand proximity, eliminating the need for bulky radar sensors while maintaining gesture detection capability

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the detection parameter from electromagnetic wave reflection (radar) to capacitance variation (capacitive sensing), enabling gesture recognition with much smaller components that have lower power consumption and smaller form factor

Inventive Principle:

Principle #35Parameter changes

3Measurement precision

If complex sensor system is used for gesture recognition, then detection accuracy is improved, but device complexity increases

Engineering Contradiction:

Improvedetection accuracyVSAvoidsystem complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts only the essential capacitive sensing function from complex radar systems, using simple plate pairs to detect gestures through capacitance changes caused by hand proximity, eliminating the need for bulky radar sensors while maintaining gesture detection capability

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the detection parameter from electromagnetic wave reflection (radar) to capacitance variation (capacitive sensing), enabling gesture recognition with much smaller components that have lower power consumption and smaller form factor

Inventive Principle:

Principle #35Parameter changes

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 capacitive sensor effectively detects air gestures with reduced space and power consumption, enabling efficient operation in electronic devices by changing capacitance values based on user interactions.

Implementation Method 1

The capacitive sensor in this application can detect an air gesture of a user based on fringe field effect

Methodology Applied

Scientific EffectFringe field effect: Electric Field

Data Source

PatentUS12136915B2Capacitive sensor, electronic device, and electronic device control method

Publication Date: 2024.11.05 HUAWEI TECH CO LTD

AI summary

A capacitive sensor, an electronic device, and an electronic device control method are disclosed and relate to the field of sensor technologies. The capacitive sensor includes at least one plate pair. Each plate pair includes a first plate and a second plate that are placed opposite to each other. A ratio of a plate length of each plate pair to a spacing in the plate pair is greater than 1 and less than or equal to 30. The capacitive sensor can detect an air gesture of a user based on fringe field effect and has advantages of a small size and low energy consumption.