Device and method for measuring gas Rayleigh-Brillouin scattering spectrum lines

Abstract

The invention discloses a gas Rayleigh-Brillouin scattering spectral line measuring device and method. A half-wave plate, a polarization beam splitter and a quarter-wave are sequentially arranged between the first laser and the beam expander. A beam combiner and a focusing lens are arranged sequentially between the polarization beam splitter prism and the photon detector; an intermediate frequency filter and an intermediate frequency amplifier are arranged sequentially between the photon detector and the photon counting card; the function signal generator is respectively connected to a photon counting card and an oscilloscope, and the photon counting card is connected to the oscilloscope and the computer respectively. The invention realizes the measurement of high-resolution atmospheric Rayleigh-Brillouin scattering spectral lines and improves the stability of the measurement. It solves the problems of difficult detection of atmospheric backscattering signals, low response rate and low signal-to-noise ratio of spectral lines, and realizes high-efficiency, high-precision and high-stability signal detection.

Description

technical field [0001] The invention relates to gas detection technology, in particular to a measurement device and method for gas Rayleigh-Brillouin scattering spectrum lines. Background technique [0002] Since Brillouin scattering was proposed for ocean monitoring in the 1960s, various researchers have realized the measurement of parameters such as sound velocity, temperature, and water volume viscosity coefficient in seawater through accurate measurement of Brillouin scattering spectrum. The lidar used for atmospheric wind field measurement is based on the Doppler frequency shift of the Rayleigh scattering Gaussian distribution spectrum of atmospheric molecules, ignoring the Brillouin scattering of atmospheric molecules, resulting in a systematic error of 3%-10%. And as early as 1968, some researchers pointed out the necessity of considering Brillouin scattering in atmospheric environment monitoring, so the research on Rayleigh-Brillouin scattering is increasing day by d...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to use the principle of optical heterodyne to solve the problem that the Rayleigh-Brillouin signal in the existing atmospheric remote sensing detection is weak, and it is difficult to achieve high signal-to-noise ratio and high spectral resolution, and to provide a gas Rayleigh-Brillouin Measuring device and method of Brillouin scattering spectrum to achieve high-precision, high-efficiency and real-time detection

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