Investigation laboratory

Physicochemical and imaging investigations

This lab is designed to carry out research, investigation, measurements and physicochemical determinations for the characterization of cultural heritage goods. The main goal is the conservation of national cultural heritage on a scientific basis and the development of new methods of patrimonialization of new archaeological finds.

Laser Induced Breakdown Spectroscopy (LIBS)

LIBS is a simple spark spectrochemical technique that has a broad capability for chemical analysis. The Andor range of iStar cameras is ideally suited to LIBS. Key features include fast or slow gating, wide spectral range, minimum insertion delay, and compact detector head. When coupled with a Mechelle spectrometer this provides a built-in diagram LIBS solution.

Laser induced Fluorescence (LIF)

LIF is a spectroscopic method used for studying the structure of molecules, detection of selective species and flow visualization and measurements. The species to be examined is excited with the help of a laser. The wavelength is often selected to be the one at which the species has its largest cross section. The excited species will de-excite after some time, usually in the order of few nanoseconds to microseconds,  and emit light at a wavelength larger than the excitation wavelength. This light, fluorescence, is measured.

Our system is designed for surface scanning and can deliver LIF distribution maps of the scanned surfaces.

Fourier Transform Infrared Spectroscopy (FTIR)

Infrared (IR) spectroscopy is one of the most important analytical techniques available to today`s scientists. Simply, it is the absorption measurement of different IR frequencies by a sample positioned in the path of an IR beam. Based on the fact that different functional groups absorb characteristic frequencies of IR radiation, the resulted spectrum can be seen as a molecular fingerprint of the sample.

Moreover, as each different material is a unique combination of atoms, no two compounds produce the exact same infrared spectrum and therefore it can lead to powerful qualitative and quantitative material analysis. Using various sampling accessories, IR spectrometers can accept a wide range of samples such as gases, liquids, and solids, with little or no preparation required.

X-Ray Fluorescence Spectroscopy (XRF)

X-ray fluorescence spectrometry is a powerful, non-invasive elemental analysis technique, used for detection of inorganic materials (elements ranging from Na up to U). Highly suitable for in-situ analysis, with no sampling required, XRF is widely used in geology, chemicals, pharmaceuticals, environmental analysis, telecommunications and microelectronics, metal finishing, fuels, recycling industry, textiles, art, and archaeology.

Among the most common applications are listed: rocks and soil characterization; chemical studies of obsidian, metals, ceramics; pigments analysis; detection of heavy metals in soil; waste processing; and so forth.

Colorimetry

Colorimetry is an investigation method that delivers essential data about the volumetric shape and the colour of the object surfaces represented by the reflection spectral curve. 

The CIE Lab colour system characterizes the colour with a luminosity parameter and two color coordinates x and y that specify the position on the chromatic diagram.

This system offers a greater precision because the parameters are depending on the spectral power distribution of the emitted light from an object’s surface and are factorized by the sensibility curves that have been measured for the human eye.

Multispectral imaging

The multi-spectral imaging camera is used for high resolution recording of material characteristic data at different wavelength and frequencies of the electromagnetic spectrum.

In the field of Cultural Heritage this technique is used in preliminary documenting, investigation and diagnosis. Theoretical aspects of multi-spectral imaging are based on the interaction of the radiation with artwork material. The available wavelengths ranges from 365 to 1100 nm covering three main domains of the electromagnetic spectrum: UV, VIS and NIR.

The multi-spectral imaging system is composed by: multi-spectral camera (CCD sensor, filters and the lenses), irradiation sources (Halogen lamps for VIS and NIR and UV lamps for UV modes) and a visualization, acquisition and data storage unit (PC with dedicated software).

Thermal imaging

Monitoring historical monuments wall temperature represents an important fact related to cultural heritage rebuilding and conservation. Regarding historical monuments field diagnosis concept refers from land to buildings, paintings, frescoes or icons located inside.

In our case, diagnosis method is based on a thermal camera. It measures and images the emitted infrared radiation from an object. The fact that radiation is a function of object surface temperature make it possible for the camera to calculate and display this temperature. First an IR picture is taken; then, aided by specialized software an ample report is realized containing detailed thermal information.

Thermal images are compared with normal ones and stored with numerical data related to wall temperature and different other calibration data of the camera. Further more dedicated data bases can built for a comprehensive vision of whole phenomena.

Laser Doppler Vibrometry

Laser Doppler vibrometry is a technique used for the identification of hidden defects. The laser beam from the LDV is directed at the surface of interest, and the vibration amplitude and frequency are extracted from the Doppler shift of the laser beam frequency due to the motion of the surface. Studied object is excited using a common loudspeaker.

Ground penetrating radar

Laser Doppler vibrometry is a technique used for the identification of hidden defects. The laser beam from the LDV is directed at the surface of interest, and the vibration amplitude and frequency are extracted from the Doppler shift of the laser beam frequency due to the motion of the surface. Studied object is excited using a common loudspeaker.