Breathing Gas Analyzer Using External Infrared Source
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gas measuring devices for respiratory gases face challenges in maintaining measurement accuracy due to changes in light power and contamination, leading to increased costs and mechanical wear, especially in mobile applications.
Innovation Solution
A gas measuring device that uses a radiation source emitting light in the 2.5 µm to 12.5 µm wavelength range, combined with a mirror arrangement, a sample gas cuvette, a light guide element, and a detector arrangement featuring bandpass filter elements and semiconductor detectors, which allows for infrared optical measurement without the need for additional beam mixing elements, reducing size and cost while enhancing light throughput and resistance to contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If additional means for lateral beam mixing are used in the beam path, then measurement accuracy is improved by compensating for lateral spatial changes in light distribution, but light throughput is reduced, device size increases, and manufacturing costs increase
Solution Approach 1:
The patent removes the light source from the sample gas cuvette and places it externally, connected via optical fibers. This extraction eliminates the need for additional lateral beam mixing means within the cuvette, reducing device complexity while maintaining measurement accuracy through the external light source configuration
Solution Approach 2:
Optical fibers serve as intermediaries to transmit light from the external source to the sample gas cuvette and from the cuvette to the detector. This intermediary approach enables accurate gas measurement without requiring complex beam mixing components inside the cuvette, thus reducing device size and component count
2Device complexity
If Fabry-Perot detectors or filter wheel sensors are used to avoid beam mixing means, then device size and cost are reduced, but moving parts are required which increase sensitivity to vibrations and shocks and cause mechanical wear
Solution Approach 1:
The patent replaces any potential moving parts with a static optical configuration using external light sources and optical fibers. The system achieves accurate gas measurement without requiring mechanical components such as filter wheels or moving detector elements, thereby eliminating mechanical wear and vibration sensitivity while maintaining reduced device size
3Measurement precision
If thermal light sources with optical shaping and sample gas cuvette are used, then measurement accuracy is maintained despite changes in light power and contamination, but manufacturing costs and device size increase
Solution Approach 1:
The light source is extracted from the sample gas cuvette and placed externally, connected via optical fibers. This simplifies the manufacturing process and reduces costs by eliminating the need for complex internal optical shaping components and thermal light sources within the cuvette, while maintaining measurement accuracy through the external configuration
Solution Approach 2:
Optical fibers act as intermediaries to transmit light with sufficient intensity and stability for accurate gas measurement without requiring expensive thermal light sources and optical shaping components inside the cuvette, thereby reducing manufacturing costs while maintaining measurement precision
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 solution provides high measurement quality with reduced sensitivity to vibrations and mechanical wear, maintaining accuracy while minimizing manufacturing costs and device size, making it suitable for mobile use.
Implementation Method 1
The absorption of light in a certain wavelength range specific for the respective gas serves as a measure for the concentration of the respective gas
Implementation Method 2
a light guide element (11) formed as a hollow body
Data Source
AI summary
A gas measuring device (1000) for determining the concentration of a gas component in a breathing gas mixture includes a radiation source (1) with a illuminant (2) and a mirror arrangement (3) for emitting light radiation. A sample gas cuvette (5) is formed as a hollow body. A detector arrangement (15) with at least two bandpass filter elements (17, 18) and at least two detector elements (20, 21) receives the filtered light radiation. A control unit (42) is configured to detect signals from the detector elements (20, 21) and determine a concentration of a gas component in the breathing gas mixture. A light guide element (11) is provided in the form of a hollow body.