PRODUCTS MODI smart
  • Instant analysis of Materials
  • Control of Industrial Processes
  • Biomedical Applications
  • Environmental Diagnostics
  • Cultural Heritage

FEATURES

  • Fast and direct analysis of solids, liquids and gases with minimum or no sample preparation
  • Articulated arm gives direct access to external samples
  • Double-pulse Nd-YAG laser, 12 ns, 120mJ, 10Hz
  • Time-integrated spectrometer, range 200)400 nm, resolution 0.04 nm
  • Extremely reproducible spectra
  • Quantitative analisys by statistical methods

MOTIVATION

LIBS allows to realize multi-elemental analysis on untreated samples. A number of applications of the LIBS technique have been recently proposed in the fields of materials science, industrial process control, environmental protection and cultural heritage conservation and study. All of these applications would benefit from mobile instruments. In a previous joint effort, Marwan Technology s.r.l. and the Applied Laser Spectroscopy (ALS) Laboratory (IPCF-CNR) in Pisa developed the first fully integrated mobile LIBS instrument. The prototype was called Modì (MObile Doublepulse Instrument for LIBS analysis). The goal of the project was to apply the LIBS technique to the world of industrial applications. Main features of the instrument were its use of double-pulse LIBS and its ability to perform standard-less quantitative analysis.

APPROACH

We have now developed a novel easy version fo Modì. The main motivation relies on the fact thet trading off system performance for lower cost, complexity and size would be convenient in several applications. The new device is a fully integrated and transportable LIBS spectrometer incorporating a dual-pulse Nd-YAG laser and a compact time-integrated spectrometer. As compared to more sophisticated systems employng echelle spectrographs with intensified CCD detectors, our device yelds a substantial reduction in the overal cost and complexity of the apparatus while featuring only slightly lower sensitivity as well as lower spectral range and resolution. Despite in principle continuous acquisition yelds much lower loise rejection than fast gating, the quality of acquired spectra seems very good as shown in the example on the right. Quantitative analysis capabilities are also quite satisfactory for many possible applications.

Detail of three LIBS spectra taken with two different steel samples: blue and red curves refer to two different runs on the same sample.

Typical LIBS spectra obtained with our prototype on an alluminum sample, using either single pulse or double pulse excitation. The comparably higher signal to noise ratio obtained with dual pulse is apparent from the spectra.  

QUANTITATIVE ANALYSIS: TEST ON STEEL STANDARD

Quantitative analysis by statistical methods has been proven to be very effective with our device. It equally applies to situations where the individual lines of the LIBS spectrum are not clearly resolved; quantitative analysis benefits from the extreme reproducibility of LIBS spectra, as illustrated in the example on the right below.
Below are shown the results of an analysis performed on 10 steel standards, using Partial Least Squares Multiple Regression and either single- or double-pulse LIBS spectra.


 
For more information on Marwan and its products, please contact us at:
Marwan: tel. +39 050 2214309 fax +39 050 2214333 e-mail: marwan@df.unipi.it
Europe: M.Tech s.a.s. tel.+39 335 6217353 e-mail: marchlor@tin.it
Italy: Lot-Oriel Italia tel. +39 06 5004204 fax: +39 06 5010389 e-mail: vitaglione@lot-oriel.it
         http://www.lot-oriel.com/site/pages_it_it/products/modi/modi.php

APPLICATION NOTES