infrared millimeter terahertz waves scientific conferences

The terahertz time-domain imaging technique is applied to investigate the internal structure of The Last Supper, a masterpiece wall painting of Leonardo Da Vinci. The experimental results show three internal layers from the surface to the depth of approximately 3 mm, which are the original painting layer with lead which preparation, and two calcium based layers. The time-domain imaging preliminary results revealed the particular internal layer structure which is not common in mural paintings by traditional fresco technique.