LIBS
Laser Induced Breakdown Spectroscopy
A laser pulse with a length of one nanosecond generates a short-lived and focused high-energy plasma burst at a defined location on the sample. The burst has a radius of 0.005 mm due to its extreme energy density. The plasma is formed from the surface material, which is deposited in a narrow area and emits light.
(The procedure is much more accurate and faster than the classical methods of X-ray fluorescence analysis. Neither radiation protection, a radiation protection officer, nor complex preparation of the sample is necessary for measurement).
The emitted light is split into its different wavelengths using a spectrometer. The light intensity of the different wavelengths is recorded in the detector and electronically processed. The sum of all spectra of the atoms contained in the sample is plotted in a wavelength diagram.
The characteristic spectra are selected and quantified. A percentage of each element contained is calculated from the total sample.
The resulting information is a qualitative and quantitative analysis of the sample’s contained elements at the point of measurement. If one element is to be measured specifically, only the wavelengths of this element are considered in the measurement.
It is also possible to exclude elements from the measurement to disregard their content in the analysis.
A special variant of quantitative determination is the analysis of compositions at different depths below a surface. For this purpose, the laser penetrates the material several times in short pulses. In this way, up to 15 times the depth of a simple measurement can be achieved. In each of the 15 depth points, the selected analysis variant is performed qualitatively or quantitatively.
