Head-Mounted Interferometric Respiration Sensing for Breathing Mode Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wearable devices face challenges in providing non-contact respiratory sensing with a small form factor while accurately measuring respiration parameters such as rate, volume, and quality, and differentiating between nasal and oral breathing.
Innovation Solution
Incorporating self-mixing interferometric (SMI) or Mach-Zender interferometric (MZI) sensors in a head-mounted device to emit electromagnetic radiation towards the user's expected airflow path, generating interferometric signals for respiration information, and using processing circuitry to determine parameters like respiration rate, volume, and breathing mode.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If interferometric sensors are used for non-contact respiratory sensing, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The system divides respiratory monitoring into multiple independent measurement domains: nasal airflow detection, oral airflow detection, and breath sound detection. Each interferometric sensor targets specific respiratory parameters, allowing the complex sensing task to be segmented into manageable components that can be processed independently
Solution Approach 2:
The interferometric sensors are designed to perform multiple functions simultaneously: detecting particle movement in airflow, measuring respiration rate, determining breath volume, and identifying breathing mode (nasal vs oral). This multi-functionality reduces the need for separate specialized sensors for each parameter
2Measurement precision
If multiple interferometric sensors are deployed to differentiate breathing modes, then measurement precision is improved, but device complexity increases
Solution Approach 1:
Different interferometric sensors are positioned at specific locations with distinct measurement characteristics: one sensor targets nasal airflow path while another targets oral airflow path. Each sensor is optimized for its specific location and function, allowing the system to differentiate breathing modes through spatially-resolved measurements rather than requiring complex sensor arrays
Solution Approach 2:
The system uses asymmetric sensor placement and configuration where sensors have different fields of view, different measurement angles, and different target regions. This asymmetric arrangement allows natural differentiation between nasal and oral breathing based on the distinct airflow patterns and particle movement characteristics detected by each sensor
3Ease of operation
If non-contact sensing is implemented, then ease of operation is improved, but measurement precision deteriorates
Solution Approach 1:
The system uses airborne particles as intermediaries to transfer respiratory information to the sensors. Instead of directly measuring airflow or breath parameters, the interferometric sensors detect the movement and distribution of particles that are naturally present in respiratory breaths, enabling indirect but accurate measurement without contact
Solution Approach 2:
The patent replaces direct mechanical contact sensing (such as flow meters or pressure sensors that require insertion into airways) with optical interferometric sensing that measures particle movement through electromagnetic radiation. This substitution maintains measurement capability while eliminating the need for physical contact with the user's respiratory system
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 non-contact respiratory sensing with a small form factor, allowing differentiation between nasal and oral breathing, and providing additional health monitoring capabilities.
Implementation Method 1
one or more interferometric sensors may be configured to emit electromagnetic radiation towards an expected airflow path for respiration of a user and generate one or more interferometric signals including information about particle movement
Data Source
AI summary
A head mounted device may include one or more interferometric sensors positioned and oriented in a housing to sense particle movement caused by respiration of a user. Interferometric signals from the one or more interferometric sensors may be used to determine respiration information about the user.