Development of a differential column image motion light detection and ranging for measuring turbulence profiles

We have developed a differential column image motion (DCIM) lidar for measuring real-time vertical profiles of Fried’s transverse coherence length (r0) and testing it against a differential image motion (DIM) lidar and a DIM monitor by observing stars throughout a range of turbulent conditions. With the DCIM lidar system parameters elaborately designed and the detector installed with an angle corresponding to the receiving telescope axis, the focal position of the laser guide star from a range of altitudes that coincide with the CCD’s receiving area, r0 of different altitudes can be obtained simultaneously. The experiment results support the DCIM lidar and confirm that a high temporal and spatial resolution r0 profile can be measured with this method.