Active pulsed thermography was applied for paintworks characterization and under surface defects analysis. Following rapid flash lamp excitation of the samples, a time-resolved thermal response in an extended infrared spectral range was recorded by two high-speed, high-sensitive mid- and long-wavelength infrared cameras. 2D phase shifts images were provided by the FFT software. The method is appropriate for rapid, remote, non-destructive characterization of various defects on painting layers and canvas, and detection of under-drawings, pentimenti, etc. Dynamic multispectral imaging in a wide infrared range may provide complementary information on cultural heritage specimens under inspection for their documentation, preservation and conservation.
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