Fig. 1. Absorption coefficients of CBrF₃， CH₂Cl₂ and CHCl₃ in the 730~790 cm^-1 band

Fig. 2. Experimental setup for acquisition of gas mixture spectra

Fig. 3. The noise of spectra at different averaging counts

Fig. 4. Quantitative analysis of mixture spectra using NLLS method

Fig. 5. Correlation analysis between transmittance spectra and single-beam spectra inversion results

Fig. 6. Correlation analysis between transmittance spectra and single-beam spectra inversion results

Fig. 7. Analysis of the correlation between the noise of spectraum and fitted residuals

Fig. 8. Error estimation and average concentration of each component's inversion results

Fig. 9. Convergence of error estimation