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Stained glasses form an important element in human history. Since stained glasses are multifunctional, they have been utilized both in religious and civil architecture. Various conservation techniques such as mechanical, chemical, and latest one being laser-based cleaning have been utilized. This work aims at making contributions to the knowledge about laser-glass interaction. The three main laser-glass interactions are photo-thermal, photo-chemical, and photo-mechanical. Experiments were carried out in burst and in continuous mode using an 800 ps n-IR laser with a wavelength of 1064nm. A pulsed/burst mode produces a sequence of a defined number of pulses with a high repetition rate. Contemporary glasses and historical pieces were used. The results realized will be important in the establishment of a laser tool selection criterion for decontamination/conservation of actual in-situ historic stained glasses and also develop a dynamic, automated, or semi-automated laser conservation method for historic glass. Complementary analytical techniques used include scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), confocal microscopy among others., Presented at the ArchMAT EMJMD Master Workshop and Fieldwork, Universidad de Burgos, Spain and the Atapuerca Archaeological Site Burgos Spain. 20th-22nd November 2019.

Stained glasses form an important element in human history. Since stained glasses are multifunctional, they have been utilized both in religious and civil architecture. Various conservation techniques such as mechanical, chemical, and the latest one being laser-based cleaning have been utilized. This work aims at making contributions to the knowledge about laser-glass interaction. The three main laser-glass interactions are photo-thermal, photo-chemical, and photo-mechanical. Experiments were carried out in burst and in continuous mode using a 800 ps n-IR laser with a wavelength of 1064nm. A pulsed/burst mode produces a sequence of a defined number of pulses with a high repetition rate. Contemporary glasses and historical pieces were used. The results realized will be important in the establishment of a laser tool selection criterion for decontamination/conservation of actual in-situ historic stained glasses and also develop a dynamic, automated, or semi-automated laser conservation method for historic glass. Complementary analytical techniques used include scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), confocal microscopy among others. The generally expected outcomes are to develop a practical criterion to apply lasers in cultural heritage; develop skills necessary to select, operate safely and apply lasers to problems in cultural heritage materials in general., This work was presented at the conference: ''Latest Technologies applied to the Conservation of Cultural Heritage: problems and solutions'' held between 25th and 27th November 2019 at the University of Zaragoza Spain.

Laser cleaning technique signifies the most noteworthy contribution of physics for artworks conservation, have been for the last three decades, functioning as a striking field of research, but with minimal attention by the archaeological conservation community. Laser-assisted removal of contamination and deterioration accumulations from archaeological bones and flints will be a unique success and highlights the use of laser cleaning methodology in practice. This presentation strives for optimizing short-pulse laser cleaning parameters for the elimination of deterioration and contamination on significant Pleistocene bones and Neogene flints surfaces from Sierra de Atapuerca (Spain), in an attempt to safeguard their archaeological value and origin. A series of studies have been carried out to assess the controlled laser cleaning parameters using two different laser systems: picosecond UV laser of 355 nm wavelength and sub-nanosecond n-IR laser of 1064 nm wavelength; taking into account both burst and continuous modes to reveal the efficiency on deterioration removal and with minimal damage to the underlying original surface. This research proposes new possibilities of using the short-pulse laser in conservation, by keeping pulse energy below the plasma formation threshold; the ablation threshold of the material could be deduced after irradiation with a series of laser pulses.