The airborne laser scan system for acquiring 3d terrain data directly is better than the conventional survey. There are the advantages of high precision, high density, and high efficient and low cost.

激光三维扫描技术可以直接获取地面三维数据，比传统测量方法具有高精度、高密集、高效率和成本低的优点。

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Canterbury City Council said the 3D laser scan being applied during the structural survey was planned as part of the year-long closure.

BBC: Canterbury's Westgate Towers get full survey