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Instruction for Operating
optoNCDT 1700
9.2 Error Influences
9.2.1 Light from other Sources
Thanks to their integrated optical interference filters the optoNCDT1700 sensors offer outstanding perfor-
mance in suppressing light from other sources. However, this does not preclude the possibility of interference
from other light sources if the objects being measured are shiny and if lower measurement frequencies 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.
9.2.2 Color Differences
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.
9.2.3 Temperature Influences
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.
9.2.4 Mechanical Vibration
If the sensor should be used for resolutions in the μm to sub-μm range, special care must be taken to ensure
stable and vibration-free mounting of sensor and target.
9.2.5 Movement Blurs
If the objects being measured are fast moving and the measurement frequency is low it is possible that move-
ment blurs may result. Always select a high measurement frequency for high-speed operations, therefore, in
order to prevent errors.
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