Optimal identification of chromium and copper by an infrared polarized radiation model
To optimize the identification of chromium and copper elements using laser-induced breakdown spectros-copy technology,a method combining infrared(IR)polarization detection theory is proposed in this paper.The generation mechanism of IR polarization was analyzed by using the Fresnel reflection law and Kirchhoff theory.The polarization characteristics of the target's IR spontaneous thermal radiation were verified in accordance with the energy conservation law.Furthermore,the plasma IR-polarized radiation signal model was derived to identify heavy-metal elements at each excitation energy based on the IR-polarized radiation transmission model and Fresnel reflection Mueller matrix,combined with the Maxwell Boltzmann distribution characteristics.The accuracy was ver-ified by five different energy-pulsed lasers.The results reveal that the IR-polarized radiation spectrum collected more characteristic signal peaks under the same laser energy,and this advantage was more prominent under low-energy excitation.Thus,the IR-polarized radiation model is a scientific and effective approach that can be used to optimize the rapid detection of heavy metals.