Fig. 1. Schematic of geometric overlap relationship of lidar

Fig. 2. Schematic of lidar lightpath layout and telescope shading cover plate device. (a) Schematic of lidar lightpath layout; (b) schematic of telescope shading cover device

Fig. 3. Entire lidar system and its U-shaped turntable structure

Fig. 4. Geometric factor processing process and results of lidar before method improvement. (a) S(Z,λ) measured by the lidar in the horizontal direction and Sfit(Z,λ); (b) geometric factors of 532 nm elastic channel in lidar

Fig. 5. Vertical occlusion measurement of 532 nm elastic detection channel echo signal before geometric factor correction and echo signal after geometric factor correction

Fig. 6. Vertical unobstructed measurement of echo signals without geometric factor correction and vertical occlusion measurement of echo signals after geometric factor correction

Fig. 7. Geometric factors of 532 nm elastic detection channel obtained by improved method

Fig. 8. Comparison of geometric factor for 532 nm elastic detection channel before and after correction

Fig. 9. Echo signals in the lidar Raman detection channel after the correction of geometric factor using improved method. (a) Correction of 386 nm nitrogen Raman echo signal; (b) correction of 407 nm water vapor Raman echo signal

Fig. 10. Comparison of extinction coefficient profiles of 532 nm wavelength aerosols before and after geometric factor correction using the improved method

Fig. 11. Optical thickness measured by lidar (532 nm) before and after improvement of geometric factor correction method and solar radiometer measurement results (550 nm)

Fig. 12. Correlation analysis results. (a) Correlation between optical thickness measured by lidar before improvement (532 nm) and optical thickness measured by solar radiometer (550 nm); (b) correlation between optical thickness measured by improved lidar and optical thickness measured by solar radiometer