Wide-band tunable cavity ring-down spectrometer

Abstract

The invention relates to a wide-band tunable cavity ring-down spectrometer. The cavity ring-down spectrometer is characterized by comprising a wide-band tunable laser light source, a light intensity adjustment system, an optical path automatic switching system, an optical resonant cavity array and a light intensity detection and data acquisition system, wherein the wide-band tunable laser light source is used for realizing the output of laser lights with different wavelengths; the light intensity adjustment system is used for unifying the light intensities of the laser lights with the different wavelengths; the optical path automatic switching system is used for enabling the laser lights, which have various wavelengths and are output by the wide-band tunable laser light source, to be emitted into corresponding optical resonant cavities in the optical resonant cavity array within a certain wavelength range; the light intensity detection and data acquisition system is used for receiving and recording the laser lights emitted by the optical resonant cavity array, and recording the wavelengths of the laser lights output by the wide-band tunable laser light source. The wide-band tunable cavity ring-down spectrometer can be used for carrying out highly sensitive detection on the optical properties of aerosol within a wavelength range of 350-870nm.

Description

technical field [0001] The invention relates to a wide-band tunable optical cavity ring-down spectrometer, and relates to the field of atmospheric environment quality monitoring. Background technique [0002] Optical cavity ring-down spectroscopy is a highly sensitive spectral detection method, which is widely used in the detection of trace gas concentration and aerosol extinction characteristics in the atmosphere. At a specific wavelength, it can absorb and detect the concentration of the gas according to the characteristic absorption of the gas. In addition, after knowing the particle size and concentration of the particle, it can also be used to detect parameters such as the extinction cross section and refractive index of the aerosol. Cavity ring-down spectroscopy is a brand-new and highly sensitive laser spectroscopy technology. Unlike traditional absorption spectroscopy, which detects changes in transmitted light intensity, cavity ring-down spectroscopy measures the sp...

AI Technical Summary

Problems solved by technology

[0003] However, most of the currently used cavity ring-down spectra are single wavelength or cover a very narrow band, which limits its wide application

A single wavelength can only be used to detect a trace gas at most, and can only give the extinction coefficient of the aerosol at this wavelength, and cannot give the spectral resolution of the optical properties of the aerosol in a wide range of wavelengths

However, the spectrum of sunlight has a wide range, and the optical properties of aerosols in different wavelength bands are not the same. For example, in the ultraviolet band, many organic aerosols have light absorption.

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