DP LIBS (DOUBLE PULSED LASER INDUCED BREAKDOWN SPECTROSCOPY) TECHNIQUE FOR THE QUALITY AND QUANTITY ANALYSIS OF CHEMICAL STRUCTURE OF OBJECT SURFACE LAYER

摘要

The invention relates to an optical electronic device for the quality and quantity analysis of the chemical composition of an object surface layer by double pulse LIBS technique. According to the invention, the device comprises an irradiation system and a detection system, the first system, the irradiation one, comprising two lasers in the Q-switched regime for the irradiation of the object to be analyzed, the beam emitted by the first laser being focused on the object surface by an optical focusing system for creating the plasma, and the beam emitted by the second laser being used for intensifying the spectral lines in the plasma by preablation or heating of the plasma; the second system, the detection one, comprises a collector for collecting the radiation emitted by the plasma which consists of a collimator to which there is coupled the optical fibre, said optical fibre being inserted into a Machelle spectrometer coupled with a ICCD detector, the information about the spectral lines provided by the ICCD detector being transmitted to a computer wherein it is stored and processed; for a good analysis of spectral lines, the irradiation process must be synchronized with the detection one, which is made by means of a pulse generator which triggers two lasers and the ICCD detector, coupled to the generator by cables.