大气相干长度是在激光大气传输和自适应光学研究中对大气湍流介质进行定量描述的重要参量。介绍了利用激光大气闪烁测量反演大气相干长度和利用差分像运动测量法(DIMM)测量光波到达角起伏方差来确定大气相干长度的两种不同测量方法,并根据光波到达角起伏和激光大气闪烁这两种不同方法测量大气相干长度的仪器,在相同的近地面传播路径上进行对比实验观测,两者测量结果有时存在一定的偏差,但其量级和时间变化趋势基本一致,这两种测量方法相互得到了验证。最后还对实验观测结果进行了讨论,分析了误差产生的原因。

The atmospheric coherence length is a very important parameter of atmospheric propagation and adaptive optics. The principle of atmospheric coherence length measurement via differential image motion measure (DIMM) angle-of-arrival fluctuation of optical wave and the measurement method dealing with the irradiance scintillation of laser propagation are introduced. The atmospheric coherence length along level propagation path is measured via differential image motion measure angle-of-arrival fluctuation of optical wave. In addition, the measurement systems dealing with the irradiance scintillation of laser propagation are used to check the results of the atmospheric coherence length measurement, and its time variation is similar, but they can be much different from each other under other conditions. Last, various errors caused by instrument are analyzed and discussed.