Analysis of the Influence of the Anti-Reflective Layer on the Accuracy Assessment of Spherical Elements Manufactured by Selected Additive Methods in the ASPECT of Optical Measurements

This article presents an analysis of the effect of an anti-reflective layer on the measurement process using the 3D GOM (ATOS II Triple Scan; currently ZEISS) optical scanner for spherical elements manufactured using four additive methods: PolyJet Modeling (PJM), Digital Light Processing (DLP), Melted Extrusion Modeling (MEM), and Direct Metal Laser Sintering (DMLS). The research focused on analyzing the effect of the anti-reflective (AR) layer on changes in numerical data and on differences that define the shape of the measured elements. It was noted that models made of light-cured resin (EC100 (DLP) and RGD720 (PJM)) were characterized by AR layer absorption, which affected the measurement results. The use of the AR layer also increases the number of points for which a fitted sphere is created in the optical scanner software for shape analysis of the research models. The application of the AR layer also affects the average dimensional deviations (relative to the MB1 and MB2 research models), most significantly for models made using the PJM and MEM methods (approx. 0.02 mm), and least significantly for models made using the DMLS method (approx. 0.004 mm). The conducted research, presented measurement results, analyses, and conclusions, will help predict the impact of using the AR layer on the measurement process and the accuracy of the obtained results of measured geometric parameters during 3D GOM (ATOS II Triple Scan) optical measurements of models made of selected materials.