1.5 μm能见度激光雷达的波长修正模型比较 The Comparison of Wavelength Dependence Models for 1.5 μm Visibility Lidar

大气能见度在大气污染监测和保障航空、航海及陆上交通安全等方面具有重要作用。1.5 μm能见度激光雷达具有人眼允许最大曝光功率大,易于实现眼安全，可实现小型化和模块化等优点，适用于人员密集的场所。大气能见度定义为当550 nm准直激光经大气衰减到出射功率的2%或5%时所传输的大气距离，因此当采用1.5 μm激光时，需要进行波长修正。本文总结了现有的几种波长修正模型，并对它们之间的差异进行了分析。为了比较各种模型，研制了1.5 μm能见度激光雷达，并在2014年10月份于安徽合肥进行了连续24小时的能见度观测。通过与前向散射能见度仪进行比较，确认Kim模型与合肥实际情况最为吻合，平均相对误差小于7.8%。 Visibility has a great effect on air pollution monitoring and all kinds of traffic operations. 1.5 μm visibility lidar has many advantages, such as eye-safe, miniaturization and modularity. Therefore 1.5 μm visibility lidar is suitable for crowded places. Visibility is defined as the atmospheric dis-tance of transmission when 550 nm collimated laser’s output power attenuates to 2% or 5%. Thus, when using 1.5 μm visibility lidar, the wavelength correction must be done. Several models have been summarized in this work, and the differences of these models have been analyzed. To have a comparison of these models, a 1.5 μm visibility lidar has been constructed. And a 24-hour continuous visibility observation is carried out in Hefei, Anhui Province in October, 2014. By comparing the data of lidar with the forward visibility meter, the Kim model is confirmed as the most suitable model for visibility measurement in Hefei and the average relative error is less than 7.8%.