Spatially registered 3D and sequentially shifted Raman mapping for painted surface characterisation

This study presents a novel platform for the non-invasive analysis of painted surfaces, integrating sequentially shifted excitation (SSETM) Raman mapping with 3D scanning. Designed for hardware-registered data acquisition, the system enables automated macro-Raman mapping across extended and uneven surfaces with precise spatial control. To demonstrate the platform potential in accurate material mapping, we showcase the results acquired from purposely prepared acrylic mock-ups and a painting. The coupling of 3D surface information with subsequent Raman spectral acquisition was exploited for precise focus adjustment and co-registration of datasets. We demonstrate the potential of combined 3D and SSETM Raman mapping—so far not implemented in cultural heritage contexts—for non-invasive analyses, even in scenarios with high fluorescent signals. The system’s modular design permits future integration of additional imaging modalities, making it a promising tool for advanced analysis in conservation science.