车载二氧化硫差分吸收激光雷达系统

Mobile SO_2 Differential Absorption Lidar System

研制了一套探测低层大气二氧化硫的车载可移动激光雷达系统.该系统选用的差分波长对为300.05nm和301.50nm.光源采用两台Nd…YAG激光器分别泵浦两台窄线宽染料激光器经过倍频来获得.激光经过合束、扩束后与望远镜同轴发射.后向散射信号被近牛顿式望远镜接收后,通过光电倍增管转换为电信号,然后被数据采集卡采集,最后用来反演二氧化硫分布廓线.在淮南地区进行了针对近地面水平探测的外场实验,结果表明,在0.8~3.0km范围内,当晚二氧化硫浓度在20μg·m-3上下波动,气象部门地面仪器结果为18~22μg·m-3,实验结果与仪器结果具有可比性.

A mobile lidar system was developed which can be used to measure the lower layer atmospheric SO2. The lasers with wavelength of 300.05 nm and 301.50 nm are adopted in this system. The laser beams, produced by two narrow linewidth dye lasers pumped by two Nd：YAG lasers, are frequency doubled by second harmonic generation crystals. They are merged, expanded and transmitted into the atmosphere coaxially with telescope. The back scattering signals are received by the Newton telescope and converted into electrical signals by photomultiplier. The data are obtained by A/D acquisition card and used to estimate the profile of sulfur dioxide. The horizontal detection were field experimented in Huainan, the results show that the mean concentration of atmospheric SO2 is about 20 μg·m-3 in the range from 0.8 km to 3.0 km. It conforms with the results of ground instrument from meteorological department whose results is about 18-22 μg·m-3.