Modern technology in artwork conservation: a laser-based approach for process control and evaluation

The present work includes a laser-based methodology for the cleaning of art works, with emphasis on the preservation of their structural integrity and identity. Modern laser-based techniques and instrumentation offer new tools in the field of artwork and antiquities conservation, aiming to alleviate the traditionally applied methods from existing weaknesses. Although in sev eral cases the use of lasers may give rise to superior results. there are s till problems to be resolved in relation to the optimization of procedures for safeguarding from potential damage. Furthermore. several operational pa rameters have to be simultaneously controlled and the long-term effects ind uced by laser irradiation must be assessed in detail before a full exploita tion of the new methods is established. The control of material removal dur ing laser cleaning is achieved by using laser-induced breakdown spectroscop y (LIBS). This control relies on the collection of spectroscopic data by LI ES, which correspond to the in-depth compositional profile of the artifact. This technique may be combined with structural analysis by holographic int erferometry. The latter is important for assessing structural changes, whic h may be induced during laser ablation. Selected examples of this type of a pplications in a carefully considered methodology are presented. (C) 2001 E lsevier Science Ltd. All rights reserved.