Type: Spectroscopic point analysis
Overview
In situ reflectance and fluorescence UV-VIS-NIR spectroscopy in the last several years has become acknowledged as an effective non invasive technique for the identification of several organic and inorganic materials used in artworks production (such as paintings, manuscripts, textiles etc). To this end, fluorescence measurements are particularly indicated for the characterization of ancient colorants as well as luminescent pigments such as zinc oxide, cadmium based pigments and also Egyptian blue. Moreover, fluorophores with similar emission spectra can be distinguished by measuring fluorescence decay lifetimes.
Technical details
The portable instrumental prototype is composed of a compact Deuterium-Halogen lamp suitable for reflectance measurements; lasers and diode laser sources for steady-state fluorescence measurements; pulsed diode lasers and LEDs for time-resolved fluorescence experiments in the ns-ms lifetime range.
They are coupled with high sensitive CCD spectrometers working in the UV-VIS-NIR which allow reflectance spectra between 200-1600 nm and fluorescence spectra in the 300-1600 nm range to be collected. Lifetimes can be measured for species emitting in the 350-850 nm spectral range.
A dedicated fibre optic system allow measurements on any surface to be done. The size of the whole probe is less than 2 mm2.
Further readings
- Romani A., Clementi C., Miliani C. and Favaro G., “Fluorescence Spectroscopy: a powerful technique for the non-invasive characterization of artworks”, Account Chem. Res., 43, 837-846 (2010).
- Romani A., Clementi C., Miliani C., Brunetti B.G., Sgamellotti A. and Favaro G., “Portable equipment for luminescence lifetime measurements on surfaces”, Applied Spectroscopy, 62, 1395-1399 (2008).
- Romani A., “Steady-state and time-resolved luminescence for in-situ characterization of polychrome artworks”, Luminescence, 23, 262-263 (2008).
Providers
MOLAB Italy: UNIPG S.M.A.Art