Measurement method of pulse laser powdery substance element based on polarization and noise reduction

Abstract

The invention provides a measurement method of a pulse laser powdery substance element based on polarization and noise reduction and belongs to the field of an atom emission light spectrum. The measurement method comprises the following steps that: a powder sample is placed on a transparent glass tray; laser which passes through the glass tray from the lower side of the glass tray is focused on a powder bottom layer so as to combust a powdery substance and generate a plasma; a radiation optical signal sent by the plasma sequentially passes through the glass tray and a polaroid to be collected by a collection lens; and then, the radiation optical signal is transmitted to a spectrograph through an optical fiber to be converted into an electric signal and then the electric signal enters a computer to be analyzed. The method disclosed by the invention does not need to press and mold the powder sample and also overcomes the fluctuation of a measured signal, which is caused by that the surface of a powder layer is not flat, so that the detection speed and the accuracy of the content of the powdery substance element are improved. Furthermore, the method further utilizes the polaroid to filter continuous background radiation in the radiation optical signal and the signal to noise ratio is improved, so that the detection limitation of the measurement is improved.

Description

technical field [0001] The invention relates to a method for measuring the concentration of elements contained in a substance, and belongs to the technical field of atomic emission spectrometry. Background technique [0002] Laser Induced Breakdown Spectroscopy (LIBS) is a brand-new material element analysis technology developed in the late 20th century, and it is a typical atomic emission spectroscopy measurement technology. The working principle of LIBS is: under the action of strong laser pulses, the material on the surface of the sample is excited to become plasma and decays rapidly. During the decay process, photons of specific frequency are radiated and characteristic spectral lines are generated. The frequency and intensity information of the sample contains the analysis object. The element type and concentration information. LIBS technology has the advantages of low operating cost, fast measurement speed, high sensitivity, no or little sample pretreatment and multi-...

AI Technical Summary

Problems solved by technology

In addition, powder samples often require a large laser energy to fully excite the plasma, but when the laser energy increases, the continuous background radiation will be strong, which affects the signal-to-noise ratio and detection limit of LIBS measurement, and also interferes with the characteristic spectrum of elements. Accurate resolution and calculation of lines

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