LASER-INDUCED BREAKDOWN SPECTROSCOPY

Laser-induced Breakdown Spectroscopy (LIBS) is an emission spectroscopy technique that provides an elemental fingerprint of the sample under investigation.

A LIBS measurement starts with an energetic laser pulse. The laser pulse is tightly focused onto the sample of interest to form a plasma. From this plasma highly discrete colors of light are emitted, called emission lines; these lines are characteristic for the elements present in the sample. A spectrometer unravels the different colors emitted from the sample and creates a spectrum. A digital camera captures the spectrum and dedicated software translates the emitted spectrum into the composition of the sample. Because all elements emit light at characteristic frequencies when excited, LIBS can in principle detect all elements, limited only by the amount of energy present in the plasma and the wavelength range of the used spectrometer.

THE BENEFITS OF LIBS ARE:

• LIBS can be applied on any type of sample: solid, liquid, and gas. It is not limited to liquids like ICP-OES or conducting solids like arc/spark emission.
• LIBS is able to determine the elemental composition of a sample with speeds exceeding 50 measurements per second. Most elemental techniques like mass spectroscopy and XRF take seconds to provide an answer.
• Unlike XRF, LIBS is able to cover the whole periodic table. Even the lighter elements like B and Li can be detected at very low concentrations.
• The LIBS plasma is generated in the open atmosphere, negating the need for large argon flows or expensive consumables which are used in ICP instrumentation.

• By using a telescope or fibers, the laser beam can be delivered to locations far away from the instrumentation. This makes LIBS suitable for the monitoring of processes in which the instrumentation cannot be placed close to the sample, such as metal furnaces or hazardous waste sites.
• Unlike most competing techniques, sample preparation is not needed for a successful LIBS measurement.
• Precise control over the laser spot size allows surface mapping and depth profiling.