In the context of this work, a prototype hybrid photoacoustic (PA) and optical system for the on-line monitoring of laser cleaning procedures is presented. The developed apparatus has enabled the detection of MHz frequency range acoustic waves generated during the laser ablation process. The intrinsically generated PA signals combined with high resolution optical images provide the opportunity to follow the cleaning process accurately and in real time. Technical mock-ups have been used to demonstrate the potential of this novel technique with emphasis given to applications that refer to the restoration of Cultural Heritage (CH) surfaces. Towards this purpose, the real time monitoring of the laser assisted removal of unwanted encrustation from stonework has been achieved using IR and UV wavelengths. This novel approach has allowed for the precise determination of the critical number of laser pulses required for the elimination of the encrustation layer, while highlighting the dominant ablation mechanisms according to the irradiation wavelength. The promising results obtained using the prototype hybrid PA and optical system can open up new perspectives in the monitoring of laser cleaning interventions, promoting an improved restoration outcome.
Development of a hybrid photoacoustic and optical monitoring system for the study of laser ablation processes upon the removal of encrustation from stonework
First published at:Feb 22, 2020
1. Cooper M. Laser Cleaning in Conservation: An Introduction (Butterworth Heinemann, Oxford, 1998).
2. Fotakis C, Anglos D, Zafiropulos V, Georgiou S, Tornari V. Lasers in the Preservation of Cultural Heritage: Principles and Applications (CRC Press, Boca Raton, 2006).
3. Siano S, Agresti J, Cacciari I, Ciofini D, Mascalchi M et al. Laser cleaning in conservation of stone, metal, and painted artifacts: State of the art and new insights on the use of the Nd:YAG lasers. Appl Phys A 106, 419–446 (2012).
4. Pouli P, Oujja M, Castillejo M. Practical issues in laser cleaning of stone and painted artefacts: optimisation procedures and side effects. Appl Phys A 106, 447–464 (2012).
5. Pouli P, Papakonstantinou E, Frantzikinaki K, Panou A, Frantzi G et al. The two-wavelength laser cleaning methodology; theoretical background and examples from its application on CH objects and monuments with emphasis to the Athens Acropolis sculptures. Herit Sci 4, 9 (2016).
6. Maravelaki P V, Zafiropulos V, Kilikoglou V, Kalaitzaki M, Fotakis C. Laser-induced breakdown spectroscopy as a diagnostic technique for the laser cleaning of marble. Spectrochim Acta Part B: At Spectrosc 52, 41–53 (1997).
7. Gobernado-Mitre I, Prieto A C, Zafiropulos V, Spetsidou Y, Fotakis C. On-line monitoring of laser cleaning of limestone by laser-induced breakdown spectroscopy and laser-induced fluorescence. Appl Spectrosc 51, 1125–1129 (1997).
8. Salimbeni R, Pini R, Siano S. Achievement of optimum laser cleaning in the restoration of artworks: expected improvements by on-line optical diagnostics. Spectrochim Acta Part B: At Spectrosc 56, 877–885 (2001).
9. Melessanaki K, Stringari C, Fotakis C, Anglos D. Laser cleaning and spectroscopy: a synergistic approach in the conservation of a modern painting. Laser Chem 2006, 42709 (2006).
10. Fortes F J, Cabalín L M, Laserna J J. The potential of la-ser-induced breakdown spectrometry for real time monitoring the laser cleaning of archaeometallurgical objects. Spectrochim Acta Part B: At Spectrosc 63, 1191–1197 (2008).
11. Ciofini D, Oujja M, Cañamares M V, Siano S, Castillejo M. Spectroscopic assessment of the UV laser removal of varnishes from painted surfaces. Microchem J 124, 792–803 (2016).
12. Moretti P, Iwanicka M, Melessanaki K, Dimitroulaki E, Kokkinaki O et al. Laser cleaning of paintings: in situ optimization of operative parameters through non-invasive assessment by optical coherence tomography (OCT), reflection FT-IR spectroscopy and laser induced fluorescence spectroscopy (LIF). Herit Sci 7, 44 (2019).
13. Fischer C, Kakoulli I. Multispectral and hyperspectral imaging technologies in conservation: current research and potential applications. Rev Conserv 7, 3–16 (2006).
14. Papadakis V, Loukaiti A, Pouli P. A spectral imaging methodology for determining on-line the optimum cleaning level of stonework. J Cult Herit 11, 325–328 (2010).
15. Pozo-Antonio J S, Fiorucci M P, Ramil A, Rivas T, López A J. Hyperspectral imaging as a non destructive technique to control the laser cleaning of graffiti on granite. J Nondestr Eval 35, 44 (2016).
16. Klemm A J, Sanjeevan P. Application of laser speckle analysis for the assessment of cementitious surfaces subjected to laser cleaning. Appl Surf Sci 254, 2642–2649 (2008).
17. Bernikola E, Melessanaki K, Hatzigiannakis K, Pouli P, Tornari V. Real-time monitoring of laser assisted removal of shellac from wooden artefacts using Digital Holographic Speckle Pattern Interferometry. In Lasers in the Conservation of Artworks 52–59 (Archetype Publications Ltd, London, 2013).
18. Márton Z, Kisapáti I, Török Á, Tornari V, Bernikola E et al. Holographic testing of possible mechanical effects of laser cleaning on the structure of model fresco samples. NDT E Int 63, 53–59 (2014).
19. Iwanicka M, Musiela J, Łukaszewicz J W, Stoksik H, Syl-westrzak M. The potential of OCT for assessing laser as-sisted removal of deposits from ceramic tiles. In Lasers in the conservation of artworks XI. Proceedings of the International Conference LACONA XI 2016 105–114 (NCU Press, 2017); http://doi.org/10.12775/3875-4.07.
20. Striova J, Fontana R, Barucci M, Felici A, Marconi E et al. Optical devices provide unprecedented insights into the laser cleaning of calcium oxalate layers. Microchem J 124, 331–337 (2016).
21. Tserevelakis G J, Siozos P, Papanikolaou A, Melessanaki K, Zacharakis G. Non-invasive photoacoustic detection of hidden underdrawings in paintings using air-coupled transducers. Ultrasonics 98, 94–98 (2019).
22. Cooper M I, Emmony D C, Larson J. Characterization of laser cleaning of limestone. Opt Laser Technol 27, 69–73 (1995).
23. Lee J M, Watkins K G. In-process monitoring techniques for laser cleaning. Opt Lasers Eng 34, 429–442 (2000).
24. Bregar V B, Možina J. Optoacoustic analysis of the la-ser-cleaning process. Appl Surf Sci 185, 277–288 (2002).
25. Jankowska M, Śliwiński G. Acoustic monitoring for the laser cleaning of sandstone. J Cult Herit 4, 65–71 (2003).
26. Gómez C, Costela A, García-Moreno I, Sastre R. Comparative study between IR and UV laser radiation applied to the removal of graffitis on urban buildings. Appl Surf Sci 252, 2782–2793 (2006).
27. Villarreal-Villela A E, Cabrera L P. Monitoring the laser ablation process of paint layers by PILA technique. Open J Appl Sci 6, 626–635 (2016).
28. Tserevelakis G J, Pozo-Antonio J S, Siozos P, Rivas T, Pouli P et al. On-line photoacoustic monitoring of laser cleaning on stone: Evaluation of cleaning effectiveness and detection of potential damage to the substrate. J Cult Herit 35, 108–115 (2019).
29. Maravelaki-Kalaitzaki P. Black crusts and patinas on Pentelic marble from the Parthenon and Erechtheum (Acropolis, Athens): Characterization and origin. Anal Chim Acta 532, 187–198 (2005).
30. Potgieter-Vermaak S S, Godoi R H M, van Grieken R, Potgieter J H, Oujja M et al. Micro-structural characterization of black crust and laser cleaning of building stones by micro-Raman and SEM techniques. Spectrochim Acta Part A: Mol Biomol Spectrosc 61, 2460–2467 (2005).
31. Vergès-Belmin V, Dignard C. Laser yellowing: myth or reality? J Cult Herit 4, 238–244 (2003).
32. Klein S, Fekrsanati F, Hildenhagen J, Dickmann K, Uphoff H et al. Discoloration of marble during laser cleaning by Nd:YAG laser wavelengths. Appl Surf Sci 171, 242–251 (2001).
33. Gaviño M, Castillejo M, Vergès-Belmin V, Nowik W, Oujja M et al. Black crusts removal: the effect of stone yellowing and clearing strategies. Air Pollution and Cultural Heritage Leiden: AA Balkema, 239–245 (2004).
34. Zafiropulos V, Pouli P, Kylikoglou V, Maravelaki-Kalaitzaki P, Luk’yanchuk B S et al. Synchronous use of IR and UV laser pulses in the removal of encrustation: mechanistic aspects, discoloration phenomena and benefits. In Lasers in the Conservation of Artworks, 311–318 (Springer, Berlin, Heidelberg, 2005).
35. Pouli P, Fotakis C, Hermosin B, Saiz-Jimenez C, Domingo C et al. The laser-induced discoloration of stonework; a comparative study on its origins and remedies. Spectrochim Acta Part A: Mol Biomol Spectrosc 71, 932–945 (2008).
36. Godet M, Vergès-Belmin V, Gauquelin N, Saheb M, Monnier J et al. Nanoscale investigation by TEM and STEM-EELS of the laser induced yellowing. Micron 115, 25–31 (2018).
37. Papanikolaou A, Siozos P, Philippidis A, Melessanaki K, Pouli P. Towards the understanding of the two wavelength laser cleaning in avoiding yellowing on stonework: a micro-Raman and LIBS study. In Lasers in the Conservation of Artworks XI, Proceedings of the International Conference LACONA XI 95–104 (NCU Press, 2017); http://doi.org/10.12775/3875-4.06.
38. Wang L V, Wu H I. Biomedical Optics: Principles and Imaging (Wiley, Hoboken, NJ, USA, 2007).
39. Simandoux O, Prost A, Gateau J, Bossy E. Influence of nanoscale temperature rises on photoacoustic generation: discrimination between optical absorbers based on thermal nonlinearity at high frequency. Photoacoustics 3, 20–25 (2015).
40. Marla D, Bhandarkar U V, Joshi S S. A model of laser ablation with temperature-dependent material properties, vaporization, phase explosion and plasma shielding. Appl Phys A 116, 273–285 (2014).
41. Feng X H, Gao F, Xu C Y, Li G M, Zheng Y J. Self temperature regulation of photothermal therapy by laser-shared photoacoustic feedback. Opt Lett 40, 4492–4495 (2015).
42. Feng X H, Gao F, Zheng Y J. Photoacoustic-based-close-loop temperature control for nanoparticle hyperthermia. IEEE Trans Biomed Eng 62, 1728–1737 (2015).
POLITEIA II(MIS 5002478), HELLAS-CH(MIS 5002735), the Stavros Niarchos Foundation
Get Citation: Papanikolaou A, Tserevelakis G J, Melessanaki K, Fotakis C, Zacharakis G et al. Development of a hybrid photoacoustic and optical monitoring system for the study of laser ablation processes upon the removal of encrustation from stonework. Opto-Electron Adv 3, 190037 (2020).
Laser physics, 2020