Device for measuring gas pressure based on Rayleigh-Brillouin scattering spectral characteristic

The invention relates to a novel method and an experiment device for measuring gas pressure based on a Rayleigh-Brillouin scattering spectrum of gas. Sound speed under different pressure intensities can be measured by detecting Brillouin frequency shift amount in the Rayleigh-Brillouin scattering spectrum at different temperatures, so the pressure can be measured. 355nm single-mode laser, 532nm single-mode laser and 1,064nm single-mode laser are emitted into the gas of a scattering pool, and interact with various gas molecules in the gas, a scattering signal passes through a Fabry-Perot (F-P) scanning interferometer and is received by a photon detector, the Rayleigh-Brillouin scattering spectrum of the gas can be obtained, and the gas pressure can be accurately measured at different temperatures by analysis and computation of a spectral function.