Uncertainty determination and quantification for dimensional measurements with industrial computed tomography

With the introduction of computed tomography (CT) for purpose of dimensional quality control, the problem has arisen of identifying the measurement uncertainty of CT-based length measurements. This paper presents a conceptual framework for CT measurement uncertainty based on the ISO-GUM, starting from the product of the voxel size and the number of voxels as the description of every CT measurement. Those two main uncertainty contributors are further subdivided and illustrated based on various measurements. Finally, this paper shows how a measurement procedure, based on voxel size and edge correction can eliminate some terms of the total uncertainty budget.