FRESCOES DIAGNOSTICS BY ELECTRO-OPTIC HOLOGRAPHY AND INFRARED THERMOGRAPHY

ABSTRACT This paper reports NDT by Electro-opticHolography and IR Thermography on a samplereproducing a wall fresco. In particular, the locationof artificial defects contained inside the fresco and the evaluation of their dimensions are examined. Animportant feature is also the classification of different kinds of defects. The experimental and dataprocessing procedures are described for both methods.In recent decades interferometric methods are increasingly being applied as diagnostic tools in theartwork conservation field. Infrared thermography is also widely applied in non-destructive diagnostics. Discontinuities oranomalous regions are located by differences in temperature. For the Thermal Method, a mathematicalsimulation of the thermal problem allows to predict thermal stresses and a better designing of the test.Automatic processing of data is presented giving outputs very simple to understand. Keywords: Optical coherent NDT, Thermal tomography, Fresco, Plaster delamination 1. INTRODUCTION