The D-800 Scanner is a high-precision mobile laser scanning system. It employs a pyramidal mirror rotating scanning technology, consisting of four sets of 90° pyramidal mirror scanning modules that collectively form a 360°scanning system. The main motor achieves a maximum rotation speed of 200 Hz. Combined with the rotation of the four-faceted pyramidal mirror within each module, a single lens can scan four lines per revolution. This configuration results in a rotational scanning mode of 800 lines per second, thereby achieving high-density point cloud coverage of 8 million points per second within the scanning range. The device is widely applicable in fields such as 3D tunnel structure inspection and existing railway survey and measurement.