Page 101
Instructions for Operating
optoNCDT 2300
10.2 Error Influences
10.2.1 Light from other Sources
Thanks to their integrated optical interference filters the optoNCDT 2300 sensors offer outstanding performance in suppressing light
from other sources. However, this does not preclude the possibility of interference from other light sources if the objects being mea-
sured are shiny and if lower measuring rates are selected. Should this be the case it is recommended that suitable shields be used to
screen the other light sources. This applies in particular to measurement work performed in close proximity to welding equipment.
10.2.2 Color Differences
Because of intensity compensation, color difference of targets affect the measuring result only slightly. However, such color differ-
ences are often combined with different penetration depths of the laser light into the material. Different penetration depths then result
in apparent changes of the measuring spot size. Therefore color differences in combination with changes of penetration depth may
lead to measuring errors.
10.2.3 Surface Roughness
Laser-optical sensors detect the surface using an extremely small laser spot. They also track slight surface unevenness. In contrast,
a tactile, mechanical measurement, e.g. using a caliper, detects a much larger area of the measurement object. In case of traversing
measurements, surface roughnesses of 5 µm and more lead to an apparent distance change.
Suitable parameters for the averaging number may improve the comparability of optical and mechanical measurements.
h > 5 µm
Max.
Min.
Ceramic reference surface Structured surface
Recommendation for parameter choice:
- The averaging number should be selected in such a way that a surface area the size of which is comparable to those with mechani-
cal measurements is averaged.
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