Designing the Spatial star as a three-dimensional derivate of the Siemens star and developing the methods to determine the accuracy, resolution and spatial frequency response from a 3D scan of the Spatial star

In many cases investigating a 3D scan of a real object is more time and cost effective than investigating the real object. This is especially the case if related objects are spread over several collections around the world. Investigation results based on a 3D scan depend on the accuracy and resolution of the specific 3D scan. This paper lays the foundation to define the specific characteristics of a workflow to determine the accuracy, resolution and spatial frequency response of any 3D scan. Therefore, it adapts the operating principle of the Siemens star to the third dimension. The result is the Spatial star, a digital three-dimensional derivate of the Siemens star that provides the required information. This paper also develops the methods to determine the accuracy, resolution and spatial frequency response from a 3D scan of the Spatial star. During this process a 3D scan is restructured into a unified matrix representation that ensures comparability between different 3D scans and fits documentation purposes. To validate the developed methods, the paper uses a set of partly simulated 3D scans of the Spatial star.