Modular Photoacoustic Gas Sensor with Removable Photonic Circuit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing miniaturized photoacoustic gas sensors face challenges such as contamination of chambers, failure of microphones, and the need for multiple laser sources, leading to high costs and the requirement for replacing entire devices for gas detection.
Innovation Solution
A modular photoacoustic detection device with a removable photonic circuit and light source, allowing independent replacement of components, and a differential Helmholtz resonator structure for improved signal-to-noise ratio and gas detection capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If a monolithic photoacoustic cell structure is used, then the device is miniaturized and integrated on silicon, but the entire device must be replaced when chambers are contaminated or microphones fail
Solution Approach 1:
The photoacoustic cell is divided into separate modular components: removable chambers that can be independently replaced, a reusable photonic circuit board containing the laser and waveguides, and replaceable microphones. This segmentation allows specific contaminated or failed components to be replaced without discarding the entire device, resolving the contradiction between miniaturization and ease of repair.
2Adaptability or versatility
If multiple laser sources are integrated to detect different gases, then detection versatility is improved, but device complexity and production cost increase
Solution Approach 1:
A single tunable laser source on the photonic circuit board can be adjusted to different wavelengths to detect multiple types of gases. The modular chamber design allows swapping chambers optimized for different gas detection ranges. This universal approach provides multi-gas detection capability without requiring multiple fixed laser sources, reducing device complexity and production cost while maintaining versatility.
3Power
If the photoacoustic cell is miniaturized, then pressure signal strength increases, but manufacturing precision requirements increase
Solution Approach 1:
The chambers are designed as standardized reusable components that can be manufactured with high precision using established microfabrication techniques. Once the optimal chamber geometry is determined, precise replicas can be produced and replaced as needed. This copying approach allows the system to benefit from miniaturization-enhanced pressure signals while managing manufacturing precision requirements through standardized component production.
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 cost-effective, efficient, and flexible gas detection without the need for multiple laser sources, reducing operational costs and extending device lifespan by allowing component-specific replacement and supporting detection of various gases.
Implementation Method 1
The principle of measuring a gas by photoacoustic effect is based on the excitation of an acoustic wave in the gas by a light source such as a pulsed or amplitude or wavelength modulated laser
Implementation Method 2
a photoacoustic cell comprising two chambers connected by two capillaries and forming a differential acoustic resonator of the Helmholtz type. Acoustic resonance is produced by exciting only one of the two chambers
Data Source
Figure 1~2A
Figure 2B~3A
Figure 3B~4A
AI summary
Modular photoacoustic detection device (100) comprising at least: - a photoacoustic cell (106) comprising at least two chambers (110, 112) connected by at least two capillaries (114, 116) and forming a differential acoustic resonator of the Helmholtz type; - acoustic detectors (122, 124) coupled to the chambers; - a light source (102) capable of emitting a light beam having at least one wavelength suitable for exciting a gas intended to be detected and modulable to a resonance frequency of the photoacoustic cell; - a first photonic circuit (104) optically coupling the light source to an entrance face (109) of a first of the chambers (110); in which the first photonic circuit is removably arranged in a first housing (108) formed in the acoustic cell and opening onto the entrance face of the first chamber.