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Optical non-destructive testing methods of cultural heritage artefacts

Optical methods are very powerful tools for non-destructive testing of works of art. There are several tasks connected with testing of works of art, which can be solved by use of optical methods, for example revealing of underdrawings in pictures, visualisation of artefacts that are due to degradation process invisible by naked eye, distinguishing between authentic and retouched parts of work of art, testing of degradation and ageing of works of art and many other tasks. In the contribution several selected optical testing methods will be described, among them ultraviolet fluorescence, infrared reflectography and laser scattering method.