Evaluation of a Budget Optical Coherence Tomography for Cleaning Treatments of Painted Ancient Artifacts

This study investigates the accuracy of a budget Optical Coherence Tomography (OCT) for measuring the thickness of protective varnishes on ancient artifacts that have to undergo cleaning or restoration. Two sets of glass slides, deposited with layers that mimic the structure of ancient handcraft objects (pigment and varnish), are analyzed. OCT measurements are compared with coating thickness gauge and destructive Scanning Electron Microscope (SEM) analysis. The results show that OCT provides reasonably accurate thickness measurements, with errors significantly lower than typical variability in cultural heritage applications. This suggests even a low-cost OCT has the potential to become a valuable non-invasive tool for real-time monitoring of cleaning treatments on ancient artifacts.