Accuracy Comparison of the Optical 3D Scanner and CT Scanner

Abstract

Regarding the very dynamic development of the non-contact measurement methods, there has been observed still increasing number of their applications in various fields during the last years -not only in the engineering industry. E.g. from the dimensional quality point of view, knowledge of real 3D data of a given part is truly very important. There are several options for obtaining these data such as the usage of optical 3D digitization or computed tomography (CT). However, within the mutual comparability of such data, it is very important to know not only the accuracy of acquiring 3D data, but also e.g. possibilities of these systems in terms of own measurement. In the paper, a specially designed part containing various convex and concave shapes was measured by using two different systems (ATOS TripleScan optical 3D scanner and METROTOM 1500 G2 CT scanner). The resulting scanned models were then compared not only in terms of dimensional accuracy, but also in terms of quality and detail of the obtained data or the time required to prepare the measurement and its implementation.

Three-Dimensional Immersion Scanning Technique: A Scalable Low-Cost Solution for 3D Scanning Using Water-Based Fluid

“…The technology behind a CT scanner involves emitting an array of X-ray beams through an object to be scanned while measuring the attenuation of the X-rays on the other side [ 4 , 5 ]. A matrix with the attenuation values acquired during the scan is the equivalent of a radon transform of a slice of that object at that particular angle [ 3 , 6 ].…”

“…A matrix with the attenuation values acquired during the scan is the equivalent of a radon transform of a slice of that object at that particular angle [ 3 , 6 ]. The CT scanner then rotates the beams around the object, repeating the process several times to generate radon transforms at different angles [ 5 ]. After turning at least 180 , these radon transforms are used to reconstruct a slice image of the original object [ 3 , 6 ].…”

Cone-Beam Angle Dependency of 3D Models Computed from Cone-Beam CT Images

“…Extraoral optical scans of a plaster model are more frequently used than X-ray CT scans because of the superior spatial resolution of 3D optical scanners. However, on the other side, both intraoral and extraoral optical scanners have limitations in scanning hidden structures between teeth such as narrow openings or cracks [ 11 , 12 ]. Therefore, an X-ray CT scan of a physical impression is now of great interest since it can provide images of the hidden and internal structures as well [ 13 ].…”

Metrological Characterization of Optical 3d Coordinate Measurement Systems – Comparison of Alternative Hardware Designs as Per Iso 10360

“…The focus was then also set on the identification of technical standards used to perform an objective metrological characterization of O3DCMS (ISO, 2021; VDI/VDE, 2012). Moreover, a list of the most commonly used artifacts was gathered (Acko et al, 2012;Eiríksson et al, 2016;Guidi, 2013;Hess et al, 2014;McCarthy et al, 2011;Mendricky & Sobotka, 2020), see Figure 1. In general, O3DCMS can be classified in three categories (Beraldin et al, 2015;Faugeras, 1993;Giancola et al, 2018;Huang & Zhang, 2006;Luhmann, 2010) depending on their working distance, namely nano/micro, close, and mid-to-long ranges.…”