The laser scanner transmits a laser beam, which is reflected by an object back to the scanner. The distance is measured with millimetre precision by means of the phase difference between the transmitted and received beams.
The mirror directs the laser beam through the space in a vertical direction. The angle is recorded at the same time as the distance measurement.
The laser scanner turns horizontally through 360° while scanning. The horizontal angle is recorded at the same time as the distance measurement.
Defining the 3D coordinates
Distance, vertical angle and horizontal angle result in polar coordinate (d, α, β), which are converted into cartesian coordinates (x, y, z).