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Instructions for Operating
optoNCDT 1402
Color Differences
9.2.2
Because of intensity compensation, color difference of targets affect the measuring result only slightly. How-
ever, such color differences 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.
Temperature Influences
9.2.3
When the sensor is commissioned a warm-up time of at least 20 minutes is required to achieve uniform
temperature distribution in the sensor. If measurement is performed in the micron accuracy range, the effect
of temperature fluctuations on the sensor holder must be considered. Due to the damping effect of the heat
capacity of the sensor sudden temperature changes are only measured with delay.
Mechanical Vibrations
9.2.4
If the sensor should be used for resolutions in the µm range, special care must be taken to ensure stable and
vibration-free mounting of sensor and target.
Movement Blurs
9.2.5
If the objects being measured are fast moving and the measurement rate is low it is possible that movement
blurs may result. Always select a high measurement rate for high-speed operations, therefore, in order to
prevent errors.
Surface Roughness
9.2.6
In case of traversing measurements a surface roughness of 5 µm and more leads to an apparent distance
change (also-called surface noise). However, they can be dampened by averaging (see Chap. 6.3).
Angle Influences
9.2.7
Tilt angles of the target both around the X and the Y axes of less than 5 ° only have a disturbing effect with
surfaces which are highly reflecting. Tilt angles between 5 ° and 15 ° lead to an apparent distance change of
approx. 0.12 ... 0.2 % of the measuring range (Fig. 22). Tilt angles between 15 ° and 30 ° lead to an apparent
distance change of approx. 0.5 % of the measuring range. These influences must be considered especially
when scanning structured surfaces. In principle the angle behavior in triangulation also depends on the
reflectivity of the target.
