Design of Non-Destructive Evaluation System for Historical Frescos with New Acoustic-Optical Method

This article outlines a non-invasive diagnostic test procedure, whose advantage is no damage to the artwork, that is based on the frequency response analysis of the acoustic excitation of the wall vibration. The detail of the test procedure for wall vibration and the system of the measurement instrument is described. Experiments were performed on a real artificial fresco in a historic vault. A two-dimensional map of surface vibration amplitudes is generated by scanning measurement points on the surface. This false-color image is then processed through image analysis techniques to determine the location and shape of the damaged area.