 Schematic LIBS Setup ( R.S. Harmon et al. Geochemistry: Exploration, Environment, Analysis, Vol. 5 2005, pp. 21–28) Laser Induced Breakdown Spectroscopy (LIBS) is a type of atomic emission spectroscopy which utilises a highly energetic laser pulse as the excitation source. LIBS can analyse any matter regardless of its physical state, be it solid, liquid or gas. Even slurries, aerosols, gels, and more can be readily investigated. And because all elements emit light when excited to sufficiently high temperatures, LIBS can detect all elements, limited only by the power of the laser as well as the sensitivity and wavelength range of the spectrograph & detector. Operationally, LIBS is very similar to arc/spark emission spectroscopy. File links The following pages link to this file: Laser Induced Breakdown Spectroscopy (LIBS) ...
File links The following pages link to this file: Laser Induced Breakdown Spectroscopy (LIBS) ...
Spectroscopy is the study of spectra, that is, the dependence of physical quantities on frequency. ...
Laser (US Air Force) A LASER (Light Amplification by Stimulated Emission of Radiation) is an optical device which uses a quantum mechanical effect called stimulated emission (discovered by Einstein while researching the photoelectric effect) in order to generate a coherent beam of light from a lasing medium of controlled purity...
Matter is commonly referred to as the substance of which physical objects are composed. ...
In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ...
Generally, an element is a basic part that is the foundation of something. ...
A typical LIBS system consists of a Neodymium doped Yttrium Aluminium Garnet (Nd:YAG) solid state laser and a spectrometer with a wide spectral range and a high sensitivity, fast response rate, time gated detector. This is coupled to a computer which can rapidly process and interpret the acquired data. As such LIBS is one of the most experimentally simple spectroscopic analytical techniques, making it one of the cheapest to purchase and to operate. YAG Yttrium Aluminum Garnet Color: Wide range of colors Moh’s hardness: 8. ...
In physics, the solid state is one of the three phases of matter (solid, liquid, and gas). ...
This article needs to be cleaned up to conform to a higher standard of quality. ...
The Nd:YAG laser generates energy in the near infrared region of the electromagnetic spectrum, with a wavelength of 1064nm. The pulse duration is in the region of 10ns generating a power density which can exceed 1GWcm-1 at the focal point. Other lasers have been used for LIBS mainly Excimer (Excited dimer) type generating energy in the visible and ultraviolet regions. Image of a small dog taken in mid-infrared (thermal) light (false color) Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than visible light, but shorter than microwave radiation. ...
The electromagnetic spectrum is the range of all possible electromagnetic radiation. ...
A nanometre (American spelling: nanometer, symbol: nm) is 1. ...
The optical spectrum (light or visible spectrum) is the portion of the electromagnetic spectrum that is visible to the human eye. ...
Ultraviolet (UV) radiation is electromagnetic radiation of a wavelength shorter than that of the visible region, but longer than that of soft X-rays. ...
The spectrometer consists of either a monochromator (scanning) or a polychromator (non-scanning) and a photomultiplier or CCD detector respectively. The most common monochromator is the Czerny-Turner type whilst the most common polychromator is the Echelle type, even so the Czerny-Turner type can be (and is often) used to disperse the radiation onto CCD effectively making it a polychromator. The polychromator spectrometer is the type most commonly used in LIBS as it allows simultaneous acquisition of the entire wavelength range of interest. A monochromator is an optical device that transmits a mechanically selectable narrow band of wavelengths of light chosen from a wider range of wavelengths available at the input. ...
Photomultipliers, or photomultiplier tubes (PMT) are extremely sensitive detectors of light in the ultraviolet, visible and near infrared. ...
A charge-coupled device (CCD) is a sensor for recording images, consisting of an integrated circuit containing an array of linked, or coupled, capacitors. ...
The spectrometer collects electromagnetic radiation over the widest wavelength range possible, maximising the number of emission lines detected for each particular element. Spectrometer response is typically from 1100nm (near infrared) to 170nm (deep ultraviolet), the approximate response range of a CCD detector. All elements have emission lines within this wavelength range. The energy resolution of the spectrometer can also affect the quality of the LIBS measurement, since high resolution systems can separate spectral emission lines in close juxtaposition, reducing interference and increasing selectivity. This feature is particularly important in specimens which have a complex matrix, containing a large number of different elements. Accompanying the spectrometer and detector is a delay generator which accurately gates the detectors response time, allowing temporal resolution of the spectrum. Juxtaposition (noun) is an act or instance of placing two things close together or side by side. ...
For alternate uses of time, see Time (disambiguation) or see TIME (magazine). ...
LIBS operates by focusing the laser onto a small area at the surface of the specimen, when the laser is discharged it ablates a very small amount of material, in the range of 1μg, which instantaneously superheats generating a plasma plume with temperatures of ~10,000°C. At these temperatures the ablated material dissociates (breaks down) into excited ionic and atomic species. During this time the plasma emits a continuum of radiation which does not contain any useful information about the species present. But within a very small timeframe the plasma expands at supersonic velocities and cools, at this point the characteristic atomic emission lines of the elements can be observed. The delay between the emission of continuum radiation and characteristic radiation is in the order of 10μs, this is why it is necessary to temporally gate the detector. Ablation is defined as the removal of material from the surface of an object by vaporization, chipping, or other erosive processes. ...
The word plasma has a Greek root which means to be formed or molded (the word plastic shares this root). ...
From ancient Greece (Ionic) An Ionian is a member of one of the four great divisions of the ancient Greek people. ...
The general meaning of atomic is irreducible. That is, reduced to the smallest possible part. ...
Look up Continuum in Wiktionary, the free dictionary Continuum can refer to: Continuum (mathematics), sets such as the real line Continuum hypothesis - There is no set whose size is strictly between that of the integers and that of the real numbers. ...
This page is about high speed motion of bodies such as airplanes through air or other fluids. ...
Because such a small amount of material is consumed during the LIBS process the technique is considered essentially non-destructive or minimally-destructive, and with an average power density of <1W radiated onto the specimen there is almost no specimen heating surrounding the ablation site. Due to the nature of this technique sample preparation is typically minimised to homogenisation or is often unnecessary where heterogeneity is to be investigated or where a specimen is known to be sufficiently homogeneous, this reduces the possibility of contamination during chemical preparation steps. One of the major advantages of the LIBS technique is its ability to depth profile a specimen by repeatedly discharging the laser in the same position, effectively going deeper into the specimen with each shot. This can also be applied to the removal of surface contamination, where the laser is discharged a number of times prior to the analysing shot. LIBS is also a very rapid technique giving results within seconds, making it particularly useful for high volume analyses or on-line industrial monitoring. Homogeneous is an adjective that has several meanings. ...
LIBS is an entirely optical technique, therefore it requires only optical access to the specimen. This is of major significance as fibre optics can be employed for remote analyses. And being an optical technique it is non-invasive, non-contact and can even be used as a stand-off analytical technique when coupled to appropriate telescopic apparatus. These attributes have significance for use in areas from hazardous environments to space exploration. Additionally LIBS systems can easily be coupled to an optical microscope for micro-sampling adding a new dimension of analytical flexibility.
Recent interest in LIBS has focused on the miniaturisation of the components and the development of compact, low power, portable systems. This direction has been pushed along by interest from groups such as NASA, ESA as well as the military. Portable LIBS systems are more sensitive, faster and can detect a wider range of elements (particularly the light elements) than competing techniques such as portable x-ray fluorescence. And LIBS does not utilise ionising radiation to excite the sample, which is both penetrating and potentially carcinogenic. The National Aeronautics and Space Administration (NASA), which was established in 1958, is the agency responsible for the public space program of the United States of America. ...
This article is about the European Space Agency. ...
X-ray fluorescence (XRF) is the phenomenon where a material is exposed to X-rays of relatively high energy, and as the X-ray (or photon) strikes an atom (or a molecule) in the sample, energy is absorbed by the atom. ...
Ionizing radiation is radiation in which an individual particle (for example, a photon, electron, or helium nucleus) carries enough energy to ionize an atom or molecule (that is, to completely remove an electron from its orbit). ...
In pathology, a carcinogen is any substance or agent that promotes cancer. ...
LIBS, like all other analytical techniques is not without limitations. LIBS is subject to the matrix effect which can be minimised by good specimen preparation and the use of accurate calibration standards, it is also subject to variation in the laser spark and resultant plasma which often limits reproducibility. The accuracy of LIBS measurements is typically better than 10% and precision is often better than 5%. The detection limits for LIBS vary from one element to the next depending on the specimen type and the experimental apparatus used. Even so detection limits of 1 to 30ppm are not uncommon, but can range from >100ppm to <1ppm. Look up Matrix in Wiktionary, the free dictionary The word matrix (plural matrices, or less often, matrixes) has several meanings. ...
In science, engineering, industry and statistics, accuracy is the degree of conformity of a measured or calculated quantity to its actual, nominal, or some other reference, value. ...
In Wikipedia, precision has the following meanings: In engineering, science, industry and statistics, precision characterises the degree of mutual agreement among a series of individual measurements, values, or results - see accuracy and precision. ...
LIBS utilises many components that are used for the vibrational spectroscopic technique of Raman spectroscopy, in fact instruments are now being designed which can conduct both LIBS and Raman without modification allowing both atomic and molecular characterisation of a specimen. The vibrational states of a molecule can be probed in a variety of ways. ...
Raman spectroscopy is a spectroscopic technique used in condensed matter physics and chemistry to study vibrational, rotational, and other low-frequency modes in a system. ...
In science, a molecule is the smallest particle of a pure chemical substance that still retains its chemical composition and properties. ...
LIBS can often be referred to as its alternative name - Laser Induced Plasma Spectroscopy (LIPS). Unfortunately the term LIPS has alternative meanings that are outside the field of analytical spectroscopy, therefore the term LIBS is preferred.
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