Fiber-optic photoacoustic sensing probe capable of resisting interference from ambient noise, and sensing system
US11940375B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Nov 26, 2021 |
| Grant date | Mar 26, 2024 |
| Priority date | — |
| Expiry date | Dec 3, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present disclosure relates to the technical field of fiber-optic gas sensing and laser photoacoustic spectroscopy, and reliability of a gas detection system is improved by actively selecting a working frequency of low noise interference combined with an optical fiber photoacoustic sensing probe capable of isolating high-frequency noise. A gas enters a photoacoustic microcavity through gaps on a sound-sensitive diaphragm after diffusing into a miniature air chamber through a plurality of micropores. Photoacoustic excitation light is incident into the photoacoustic microcavity through a fiber-optic collimator and then excited to generate a photoacoustic pressure wave to cause the sound-sensitive diaphragm to vibrate periodically. An end face of a single-mode optical fiber and the sound-sensitive diaphragm constitutes a fiber-optic Fabry-Perot interferometer. The interferometer measures a deflection of the diaphragm and inverts a concentration of the to-be-measured gas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.