3.6.3
Direction measurement
The emitted laser beams are deflected by an internal rotating mirror and scan the
environment in a circular motion. The measurements are triggered by an encoder in
regular angle increments.
The LMS5xx PRO/Heavy Duty measures with an adjustable scanning frequency of 25,
35, 50, 75 or 100 Hz. A laser pulse and thus a measurement is triggered continuously
after each angle increment of 0.1667°, 0.25°, 0.33°, 0.5°, 0.6667° or 1°.
In interlaced mode, the start angle of a measurement is cyclically shifted in order to
achieve an even finer angular resolution
see "Interlaced mode", page 29
The LMS5xx Lite scans at a scanning frequency of 25, 50 or 75 Hz and with angle
increments of 0.25°, 0.5° or 1°.
3.6.4
Impact of object surfaces on the measurement
The received signal from a perfectly diffuse reflection from a white surface (diffuse
Lambertian reflector) corresponds to a remission of 100%. By this definition, surfaces
that reflect the light in bundles (specular surfaces, reflectors) have remissions of over
100%.
Reflection
Most surfaces produce a diffuse reflection of the laser beam in all directions. The
structure (smooth or rough), shape (flat or curved), and color (light or dark) of the
surface determine how well the laser beam is reflected.
On very rough surfaces, a large proportion of the energy is lost due to absorption.
Curved surfaces produce a higher diffusion. Dark surfaces reflect the laser beam worse
than light ones (brilliant white plaster reflects approx. 100% of the light, while black
foam rubber reflects approx. 2.4%). The aforementioned surface characteristics can
reduce the scanning range of the device, in particular for surfaces with low remission
values.
Figure 6: Reflection of light on the surface of the object
Angle of reflection
The angle of reflection corresponds to the angle of incidence. If the laser beam hits
a surface at right angles, the energy is optimally reflected. If the laser beam hits a
surface at an oblique angle, energy and range are lost accordingly.
3
PRODUCT DESCRIPTION
18
O P E R A T I N G I N S T R U C T I O N S | LMS5xx
8013796/1ALS/2021-03 | SICK
Subject to change without notice
