When a three-dimensional laser scanning device is used at a civil engineering construction site, a point cloud density of laser beam per unit area is greatly different between a nearby area of the device and a far end, which increases the number of measurement and the amount of time for measurement to satisfy the accuracy of distance measurement. In the three-dimensional laser scanning device, an axis around which a body rotates or rotatably moves is tilted to intersect with a direction perpendicular to a measurement surface. A control unit gradually reduces an angular velocity of the rotation or the rotatable movement of the body around the axis with an increase of a distance to the measurement point to keep the point cloud density of laser beam projected onto the measurement surface constant.
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