Breath Sensor Using Surface Potential Change for Moisture Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing breath sensors that detect presence or absence of breath based on temperature changes are susceptible to external temperature environments, leading to inaccurate evaluations.
Innovation Solution
A breath sensor design featuring a base body with first and second electrodes, where the second electrode is covered by a moisture-impermeable layer, utilizing a cation or anion exchange membrane base body whose surface potential changes with moisture attachment, allowing for detection of breath frequency and moisture content through potential difference measurement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If temperature-based detection is used to evaluate breath presence, then the sensor structure is simple, but the measurement accuracy deteriorates due to susceptibility to external temperature environment
Solution Approach 1:
The patent changes the detection parameter from temperature to surface potential. The base body material's surface potential changes in response to moisture attachment from breath, and this potential change is detected by electrodes to determine breath presence. This parameter change eliminates susceptibility to external temperature environment while maintaining simple sensor structure.
Solution Approach 2:
The patent replaces the thermal detection mechanism with an electrostatic detection mechanism. Instead of measuring temperature changes, the system uses electrodes to detect surface potential changes on the base body caused by moisture attachment, substituting thermal field measurement with electrical field measurement.
2Reliability
If a covering layer is added to protect the second electrode, then the electrode protection is improved, but the device complexity increases
Solution Approach 1:
The patent divides the sensor into distinct functional regions: a first electrode region exposed to breath for detection, and a second electrode region covered by a moisture-impermeable layer for reference potential. This segmentation allows each electrode to serve its specific function while maintaining overall system simplicity.
Solution Approach 2:
The moisture-impermeable covering layer acts as an intermediary between the second electrode and the breath environment. It protects the second electrode from moisture while allowing the electrode to function as a stable reference, mediating between the need for protection and the need for electrical functionality.
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 accurate detection of breath presence and moisture content in breaths, independent of temperature environments, with improved responsiveness and accuracy compared to temperature-based sensors.
Implementation Method 1
the base body being made of a material whose surface potential changes due to attachment of moisture to the surface of the first electrode and/or the outer surface of the base body
Implementation Method 2
a covering layer made of a material that does not pass moisture there through, the covering layer covering the second electrode
Data Source
AI summary
A breath sensor includes a base body, a first electrode provided on a part of a surface of the base body, a second electrode provided on a part of the surface of the base body, and a covering layer made of a material that does not pass moisture therethrough, the covering layer covering the second electrode with the base body. The base body is preferably made of a material whose surface potential changes due to attachment of moisture to one of a surface of the first electrode and the surface of the base body. A surface potential on a side of the first electrode of the base body changes when a breath containing moisture touches the surface of the first electrode.