**1. Introduction**

130 Advanced Aspects of Spectroscopy

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(2): 179-88. Epub 2008 Mar 3.

Wiley (1979).

[20] Mathcad, version 14.0.0.163 Copyright © 2007 Parametric Technology Corporation. All

[21] Pething, 1979 R. Pething. Dielectric and Electronic Properties of Biological Materials,

[22] Awad S., Allison S.P., Lobo D.N., "The history of 0.9% saline.", Clin. Nutr. 2008 Apr; 27

Laser-induced breakdown spectroscopy (LIBS) is an atomic emission spectroscopy. Atoms are excited from the lower energy level to high energy level when they are in the high energy status. The conventional excitation energy source can be a hot flame, light or high temperature plasma. The excited energy that holds the atom at the higher energy level will be released and the atom returns to its ground state eventually. The released energy is welldefined for the specific excited atom, and this characteristic process utilizes emission spectroscopy for the analytical method. LIBS employs the laser pulse to atomize the sample and leads to atomic emission. Compared to the conventional flame emission spectroscopy, LIBS atomizes only the small portion of the sample by the focused laser pulse, which makes a tiny spark on the sample. Because of the short-life of the spark emission, capturing the instant light is a major skill to collect sufficient intensity of the emitting species. Three major parts of the LIBS system are a pulse laser, sample, and spectrometer. Control system is usually needed to manage timing and the spectrum capturing. Figure 1 illustrates those three major components and a computer in the conventional LIBS.

The LIBS has been used for the materials detection and analysis in various applications, such as steel and alloys[1-8], paints and coatings[9-15], wood pre-treatment[16], polymers [17], bacteria[18], molds, pollens, and proteins[19,20], and space exploration[21]. The great majority of LIBS results were consolidated in the reviews[22] and books[23, 24].

In spite of its advantage in analytical spectroscopy, LIBS application is still restricted within certain areas and propagation of the technology is not very wide. Many laboratory LIBS systems are built in schools, research labs and companies with discrete optical parts. Their pioneering approach in the new application seemed promising for a certain samples, but actual use in the application field is usually very limited. We can explain the situation with other analytical techniques, for example, Gas Chromatography (GC). The GC can separate the volatile species. However, one GC setup can work for a narrow range of species grouped in the sample. For different applications, the user must change the GC column, detector,

© 2012 Kim and Lin, licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2012 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

**Figure 1.** The conventional LIBS system configuration

carrier gas or at least use a new column temperature cycle. The application of LIBS also needs case-by-case adjustment. Many new applications start with looking at the advantages of LIBS and choosing a LIBS setup, and it still needs a detailed investigation for successful analysis.

This chapter describes how the LIBS system works and explains the major parts of LIBS to select specific functional requirements for its intended application. The three major parts: laser, sample and spectrometer are explained. The laser provides the breakdown energy and plasma generation. Analytical sample is the target of the laser shot and the source of emission species. The spectrometer comprises detection system with light detector and computer. Their disadvantages and limitations are discussed then suggesting how to select the equipment type and configuration to maximize the advantages of LIBS. This will provide a beginning inspiration of LIBS systems to install and apply the desired specific analytical purpose or application area.
