Assessing the optical configuration of a structured light scanner in metrological use

Structured light scanners for three-dimensional surface acquisition (SL scanners) are increasingly used for dimensional metrology. The optical configuration of SL scanners (focal length and baseline distance) influences the triangulation process, on which the scanners' measurement principle relies. So far, only a limited number of studies has investigated the optical configuration's influence on the accuracy of a SL scanner. To close this gap, this work presents a design of experiment in which the optical configuration of a SL scanner is systematically varied and its influence on the accuracy evaluated. Further, tactile reference measurements allow to separate random from systematical errors, while a special test specimen is used in two different configurations to ensure general applicability of the findings. Thus, this work provides support when designing a SL scanner by highlighting which optical configuration maximizes accuracy.