Calibration Methodology for Laser Scanner External Parameters
2. CHARACTERISTICS OF LASER SCANNER
2.1 Laser Scanner
Laser scanner is operated by measuring the time flight of laser light pulse. A pulsed laser beam
is emitted and reflected. After laser beam meets an object, the reflection is received. The time
between transmission and reception is proportional to the distance between laser scanner and an
object. The laser beam is deflected by an internal rotation mirror. A fan-shaped scan is made of
the surrounding area. The contour of the target object is determined from the sequence of
impulses received. In this research, LMS-291, SICK, is used. Table 1 shows basic specifications
of LMS-291.
Table 1 Specification of LMS-291
2.2 Spot Diameters and Intervals
In a radial field of vision, a light impulse is emitted every 0.25º in this research. As a result of
the beam geometry, the spots overlap on the target object. Figure 1 shows spot diameters and
intervals in relation to the range.
Figure 1 Diameter and Interval of Spot
