The radiative deactivation pathway of a molecular electronic excited state is characterized by a fast kinetic, ranging from picoseconds to few seconds, that leads to the ground state recovering. Using a pulsed excitation source, it is possible to measure the kinetic parameter of the fluorescence decay which is called lifetime. In the occurrence of fluorophores with similar emission spectra, the fluorescence decay lifetimes can be exploited for distinguished fluorescing materials.
archaeological object and site, architecture, art, decorative arts, manuscript, musical instrument, painting, papyrus, photo, sculpture, textile
The portable instrumental prototype is composed of pulsed diode lasers and LEDs at 375, 450 and 630 nm in the ns-ms lifetime range coupled with high sensitive photocatod working in the 350-850 spectral rgion which allow time-resolved fluorescence experiments to be performed. A dedicated fibre optic system allow measurements on any surface to be done....