The on‐site/remote Raman analysis with mobile instruments: a review of drawbacks and success in cultural heritage studies and other associated fields

Abstract

The miniaturisation of laser sources, charge‐coupled device electronic control boxes and increasing Lap‐top computer capacity led to a revolution in Raman spectrometry: Measurements can be made outside the laboratory with transportable, mobile and ultramobile instruments, even in severe conditions (e.g. rock shelter in mountains). However, many specific difficulties must be previously solved: The variety of mobile laser sources remains limited to red and green excitations, the positioning/focusing and protection against solar/bulb lighting are difficult and, more importantly, the spectral resolution and spectral window are limited. Nevertheless, the definition of good procedures and the use of advanced optics allow the on‐site analysis of various cultural heritage materials: pigments of pastels, miniatures, drawings, glasses, enamels and glazes, rock art, crystalline and amorphous phases of pottery, enamelled glass artefacts or stained glasses, bronze and brass patinas, etc. Simultaneously, mobile instruments equipped with a telescope and pulsed Yttrium Aluminum Garnet laser are being implemented for planetary mission (Mars). The present state of the art and future development are discussed. Copyright © 2012 John Wiley & Sons, Ltd.

Raman Spectroscopy of Microbial Pigments

“…Therefore, the development of miniaturized instruments and their exploitation for the analysis of geological samples on Earth will prepare the possible future deployment of Raman instruments to test for pigments such as carotenoids deposited by extinct or extant organisms in the Mars regolith (9,34,35,62,63,(111)(112)(113)(114)(115)(116)(117)(118). Very recent publications review the state of the art of the use of portable and handheld Raman instruments and experience using these instruments (119)(120)(121).…”

A multi-technique approach, based on mobile/portable laser instruments, for the in situ pigment characterization of stone sculptures on the island of Crete dating from Venetian and Ottoman period

“…The basis for identifying different materials derives from the characteristic vibrational modes of molecules/materials and their corresponding frequencies, which are recorded in Raman spectra. These frequencies are highly specific enabling one to discriminate hardly distinguishable materials [8,9] or even different crystal phases of the same minerals [10]. A number of compact Raman micro-spectrometers are at present commercially available, while laboratory prototypes are also in use for specific applications.…”

Comparing the effectiveness of hyperspectral imaging and Raman spectroscopy: a case study on Armenian manuscripts

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