Fig. 1. Schematic of analyzing process

Fig. 2. Simulation results of the flat field holographic concave grating

Fig. 3. Schematic of spectral analysis system configuration

Fig. 4. Spectral range and calibration results of the spectrometer prototype. (a) Wavelength range; (b) calibrated spectral curve

Fig. 5. Hg lamp resolution test curve

Fig. 6. Test results of system stability. (a) 12 sets of test data chart; (b) 12 h test data scatter chart

Fig. 7. Gas detection and analysis system. (a) Physical picture of test system; (b) deuterium lamp-ultraviolet spectrometer measurement system

Fig. 8. Absorption spectrum of SO₂ gas and filtered SO₂ differential absorption cross section at 215-238 nm and 290-311 nm