(i) Infrared spectroscopy.
The laboratory is equipped with a spectrometer of the house Perkin-Elmer with a Fourier Transform, suitable for operation in the middle and near infrared. Specifically, the device consists of:
- a microscope equipped with a white light source (LED Illumination) and a high-performance detector with liquid nitrogen cooling, which allows to receive spectra from very small samples (size range 10-20 mm)
- a high performance spectrometer compatible with 'plug-and-go' peripheral components
- a computer with the appropriate operating software installed for the handling of apparatus that allows the automatic selection or control mode (transmission or reflectance mode), of the sources, the lasers, the detectors, the interferometer, as well as the automatic receipt and processing of spectra, and their analysis and assessment.
The system of infrared spectroscopy is accompanied by peripheral components such as:
- component for measuring the attenuation of total reflectance (micro-ATR - Attenuated Total Reflection) through straightforward adaptation to the microscope for studies of a wide variety of samples without the need of sample preparation with KBr and press
- component for measuring diffuse reflectance suitable for studying in macroscopic scale of samples in powder form.
- component for permeability measurements (transmittance) suitable for studying in macroscopic scale of samples in the form of thin films..
(ii) Micro-Raman spectroscopy.
The laboratory is equipped with a Raman dispersion spectrometer of house Renishaw, suitable for sample measurements in the spectral range of 60-7000 cm-1. The spectrometer is equipped with::
- one CCD detector (Charge Coupled Device)
- a microscope accepting lenses of magnification 5x, 20x, 50x and 100x, which allows to obtain spectra from very small samples (size range 2-3 μm)
- two lasers emitting three excitation beams with a wavelength of 488, 514 and 785 nm
- a computer having the appropriate operating software installed for handling the instrument that allows the automatic selection or control of the operation of lasers and the corresponding excitation beams, the detector, and performing automatic spectra acquisition and processing, analysis and evaluation
The system of micro-Raman spectroscopy has peripheral components such as:
- polarizer-analyzer pairs, which allow obtaining spectra in various scattering geometries
- a lens and mirrors system able to move freely in space, giving the ability to get spectra from the surface of very large samples which are difficult to be placed directly under the microscope.
The laboratory performs analyzes of organic and inorganic materials been used in religious objects (icons, wall-paintings, manuscripts, textiles, etc.) and objects of cultural heritage in general.
More specifically, the workshop focuses on the following areas:
- Characterization and identification of organic and inorganic materials used in cultural heritage.
- Study of the lesions and the aging mechanisms which affected these materials.
- Exploring the technical construction of objects of cultural heritage in respect to the technology of each era.