Fig. 1. Optical structure of spatial heterodyne Raman spectrometer

Fig. 2. Angular distribution and Raman spectrum. (a) Angular distribution for each diffraction order; (b) Raman spectrum of monochromatic light under multistage diffraction

Fig. 3. Multiple-wavelength noise superposition. (a) Signal noise of 1120 nm and 1130 nm; (b) signal noise of 1110 nm, 1120 nm, 1130 nm, and 1140 nm

Fig. 4. Distribution of stray light sources

Fig. 5. Partial light path in 0° FOV

Fig. 6. Position of G2 stop

Fig. 7. Schematic of light trap

Fig. 8. Position of light trap for compensating light leakage

Fig. 9. Positions of light traps and baffles

Fig. 10. Light path after stray light control

Fig. 11. Raman spectra before and after stray light control in 0° FOV. (a) Before control; (b) after control

Fig. 12. Spectra in different FOV ranges. (a) FOV of ±1.3°; (b) FOV of ±2.5°

Fig. 13. Schematic of field stop

Fig. 14. Spectra in multiple FOVs after control. (a) FOV of ±1.3°; (b) FOV of ±2.5°

Fig. 15. Structural diagram of system

Fig. 16. Interference fringes