The key feature is the adjustment of the energy density ratio of the two beams (i.e. UNIT-2, which refers to laser-assisted removal of complicated cleaning on the basis of double wavelength Nd:YAG lasers is based on:Ī QS Nd:YAG laser emitting in different frequencies (1064nm, 532nm, 355nm, etc.) specially modified to use synchronously two of the wavelengths in spatial and temporal overlapping offers a convenient basis to exploit the possibility to combine the different cleaning mechanisms (i.e. Larger objects may be hosted upon discussion and planning. Max dimension of paintings with the current unit geometry: 50 cm x 50 cm. These can be selected according to the specifications of each individual cleaning case and may be one or more of the following: Spectral Imaging to visualise the cleaning state, Laser-Induced Fluorescence (LIF) to evaluate the thinning of varnish, Vis – NIR Diffuse Reflectance spectroscopy to chemically characterise the irradiated surfaces, Photoacoustic sensors to monitor the cleaning process, and so on. A number of multi-modal diagnostic instruments for in-situ assessment of the cleaning result and monitoring of the laser ablation procedure.On the basis of a well-defined protocol, this computer-driven mechanized component enables the homogeneous scanning of a predefined area, and A beam guiding system that delivers/directs the laser beam (of adjustable fluence, size and repetition rate) onto the painting surface.UNIT-1, which is dedicated to the laser-assisted reduction of aged/polymerised organic coatings (varnish, protection films, etc.) from paintings is composed of: aged varnish layers or over-paintings from paintings.pollution or burial encrustations from stone sculptures,.Removal of unwanted layers from original surfaces, such as Additionally, a laser cleaning support station equipped with glovebox and exhaust hood for handling materials producing emissions of dust or volatiles has been also developed at the laboratory. A number of laser cleaning accessory workstations have been developed at FORTH in order to handle the different types of conservation problems individually and approach the various laser cleaning challenges, such as a computer-controlled beam steering system for a high precision smooth laser scanning over the object (for the cleaning of paintings and large flat/homogeneous surfaces) and a XY motorized, computer-controlled stage for translating the object with respect to the laser beam. The unique facilities offered by PhoHS-FORTH over the past 25 years embrace several laser systems operating at different wavelengths, pulse durations and modes, dedicated assessment and evaluation facilities and a highly experienced team of experts in the field. The goal of FIXLAB facility at FORTH (PhoHS-FORTH) is to respond to diverse conservation and cleaning challenges by developing and implementing optimum laser cleaning methodologies for CH assets followed with dedicated methodologies for the assessment of the treated surfaces and the monitoring of the cleaning interventions. Access provider: Photonics for Heritage Science, IESL Title : Laser conservation Description
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |