Non-invasive investigation of art paintings by terahertz imaging
Résumé
Terahertz electromagnetic waves propose attractive features such as non-invasive and non-destructive analysis, transparency and good penetration depth through various materials, low scattering and broad spectral bandwidth. In this paper, we demonstrate the capability of terahertz imaging for the investigation of art paintings. The imaging system is able to reveal buried layer information such as a graphite handmade sketch covered by several layers of painting. In addition, taking advantage of the pulsed terahertz emission, we show that it is also possible to evaluate the variations of the painting thickness.