Laser-induced breakdown spectroscopy

The laser-induced plasma spectroscopy, abbreviated LIBS ( laser -induced english of breakdown spectroscopy ) is a laser - spectroscopic method to determine the composition of a sample. Due to its relative simplicity it is widespread. It is a variant of atomic emission spectrometry.

Principle of operation

By a laser pulse to the sample, a small volume is to be ionized, a plasma ( laser ablation). That is why light emitted is characteristic of the particular material. The radiation is absorbed by glass fibers and fed to a spectrometer.

From the intensity spectrum of the atomic composition of the sample can be determined. In order to determine the molecular composition, the spectrum must be measured with time resolution.

Advantages over other methods of analysis

The laser-induced plasma spectroscopy requires no sample preparation and works relatively non-destructive. It allows for the qualitative and quantitative determination of the atomic composition of a sample simultaneously for all elements.

Disadvantages

In practice, the calibration caused the greatest difficulties, in many cases, the calibration is only approximate. In the analysis of materials that are non- homogeneous mixtures, such as Ores, consuming sample preparation must be operated.

Two laser pulses in order to reduce the detection limits used sometimes. Ideally, the extraction is performed with the first short pulse of ultraviolet light and heat, in addition to the second, longer plasma.

Areas of application

A ChemCam called instrument is used by the Curiosity rover on Mars.