Laser-induced breakdown spectroscopy (LIBS) is a type of atomic emission spectroscopy which uses a highly energetic laser pulse as the excitation source. Laser-induced plasmas are finding increasing interest as sources of materials resulting from the ablation of the target (called laser ablation or LA) and also of. Laser-induced breakdown spectroscopy (LIBS) has been invented for . Elementary processes in a laser-induced plasma in an ambient gas.
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This analytical technique offers many compelling advantages compared to other elemental analysis techniques. A sample preparation-free measurement experience Extremely fast measurement time, usually a few seconds, for a single spot analysis Broad elemental coverage, including lighter elements, such as H, Be, Li, C, N, O, Na, and Mg Versatile sampling protocols that laser induced plasma fast raster of the sample surface laser induced plasma depth profiling Thin-sample analysis without the worry of the substrate interference A typical detection limit of LIBS for heavy metallic elements is in the low-PPM range.
Laser-induced breakdown spectroscopy - Wikipedia
LIBS is applicable to a wide range of sample matrices that include metals, semiconductors, glasses, biological tissues, laser induced plasma, plastics, soils, plants, soils, thin-paint coating, and electronic materials. So how does LIBS work?
The main physical process that forms the essence of LIBS technology is the formation of high-temperature plasma, induced by a short laser pulse. When the short-pulse laser beam is focused onto the sample surface, a small volume laser induced plasma the sample mass is ablated i.
The most common monochromator is the Czerny—Turner type whilst the most common polychromator is the Echelle type.
However, even the Czerny-Turner type can be laser induced plasma is often used to disperse the radiation onto a CCD effectively making it a polychromator. The polychromator spectrometer is the type most commonly used in LIBS as it laser induced plasma simultaneous acquisition of the entire wavelength range of interest.
The spectrometer collects electromagnetic radiation over the widest wavelength range possible, maximising the number of emission lines detected for each particular element.
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 juxtapositionreducing interference and increasing selectivity.
Electrolaser - Wikipedia
This feature is particularly important in specimens which have a complex matrixcontaining a large number of different elements. Accompanying the spectrometer and detector is a delay generator which accurately laser induced plasma the detector's response time, allowing temporal resolution of the spectrum.
Advantages[ edit ] 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 less than one watt radiated onto the specimen there is almost no specimen heating surrounding the ablation site.
Due to the laser induced plasma 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 homogeneousthis laser induced plasma 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. laser induced plasma
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LIBS is also a very rapid technique giving results within seconds, making it particularly useful for high volume analyses or on-line industrial monitoring.
LIBS is an entirely optical technique, therefore it requires only optical access to the specimen. This is of major significance as fiber optics can be employed for remote analyses. And being an optical technique it is non-invasive, laser induced plasma and can even be used as a stand-off laser induced plasma technique when coupled to appropriate telescopic apparatus.
Laser-induced breakdown spectroscopy
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.
As a weapon, to make a thunderhead deliver a precise lightning strike onto a target from an aircraft; in this case, the aircraft and laser can be compared to a triggered spark gapin that the relatively minor amount of initial input from the laser allows a large amount of energy to laser induced plasma between laser induced plasma cloud and the ground.
Because of the plasma channelan electrolaser may cause an accident if there is a thunderstorm or other electricity sources such as overhead powerlines about. An electrolaser is not presently practical for wireless energy transfer due to danger and low efficiency.
Future designs include weapons mounted on land, air and sea vehicles and as a hand-held infantry version.