Fig. 1. Diagram of multi-longitudinal-mode high spectral resolution lidar system based on Mach-Zehnder interferometer

Fig. 2. Relationship between effective transmittance of Mie signal and O_PD in aerosol channel. (a) Only the matching of O_PD and the double length of cavity is considered; (b) only the matching of O_PD and laser wavelength is considered

Fig. 3. Diagram of lightpath of MZI (divergence angle is not 0°)

Fig. 4. Change curve of T_aa with divergence angle

Fig. 5. Diagram of lightpath of field-widening of large optical path difference MZI

Fig. 6. Additional O_PD varies with divergence angle before and after the field-widening. (a) Before field-widening; (b) after field-widening

Fig. 7. Interference patterns of MZI at different divergence angles. (a) 0 mrad; (b) 1.0 mrad; (c) 2.0 mrad; (d) 3.0 mrad; (e) 4.0 mrad;(f) 5.0 mrad

Fig. 8. Change curve of interference intensity of MZI with δOPD

Fig. 9. T_aa varies with divergence angle before and after field-widening