Tuning fork resonance enhanced double-optical comb multi-component gas detection system

Abstract

The invention provides a tuning fork resonance enhanced double-optical comb multi-component gas detection system which comprises two optical comb laser sources, a polarization controller, a beam combiner, a half-wave plate, a photoacoustic gas cell, a focusing lens, a tuning fork receiver group, a multi-channel ADC (Analog to Digital Converter) unit and a frequency spectrograph. The invention discloses a tuning fork resonance enhanced double-optical comb multi-component gas detection method. The method comprises the steps that a coherent optical comb source with stable time frequency is adopted as a wide-band excitation source to excite various gas molecules to generate different photoacoustic signals; the frequency of the photoacoustic signals are determined by the beat frequency between the comb teeth of the two optical combs; different photoacoustic signals are subjected to resonance enhancement by using tuning forks with different characteristic frequencies in the tuning fork group, so that the purpose of improving the spectrum detection sensitivity of the double optical combs is finally achieved, and the problem of a non-contact gas detection technology in the aspect of high-sensitivity multi-component gas spectrum testing is solved.

Description

technical field [0001] The invention relates to the technical field of gas detection, in particular to a dual-comb multi-component gas detection system and method enhanced by tuning fork resonance. Background technique [0002] With the continuous development and progress of society, the types and quantities of gases that are exposed to and used in various fields are increasing, and the demand for testing the composition and content of related gases is also increasing. Some dangerous gases, such as explosive gases or toxic gases, are used in industrial production, so real-time monitoring of dangerous gases is required to avoid accidents. In daily life, it is also necessary to detect harmful gases in order to take relevant measures, such as detecting harmful gases such as formaldehyde in newly renovated houses, carbon monoxide in the air, and nitrogen oxides. In biomedicine and other fields, there is also an urgent need to detect related gases, such as monitoring the ethylen...

AI Technical Summary

Problems solved by technology

It has the advantages of small size, high sensitivity, fast response, easy integration, and low cost. Its disadvantages include: dispersion, temperature instability, and easy interference.

Advantages of gas chromatography: detection of more gases and high detection sensitivity; disadvantages: hydrolysis may occur during sampling and analysis, and SO 2 The detection is difficult, the detection time is long, and it cannot be detected online in real time

Its advantages: the measurement spectrum is wide, can cover the key mid-to-far infrared bands, and can realize online detection; disadvantages: limited spectral resolution, such as SF 6 It is close to the absorption peak of its decomposition gas and is difficult to be distinguished, so cross-interference will occur and affect the measurement results. In addition, due to the use of mechanical scanning measurement methods, its inspection time-consuming and low sensitivity

Because of the low coherence and stability of the infrared light source, this method also has the following disadvantages: low detection accuracy, low resolution, poor repeatability, and it is difficult to simultaneously measure the absorption peaks of multi-component gases

However, due to the wide spectrum and energy dispersion of the optical comb, the detection sensitivity of this method is low, and it cannot be compared with the above-mentioned traditional gas detection technologies.

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