System parameters are important factors that affect the spatial characteristics of laser induced plasma spectral intensity. In this paper, a two-dimensional LIBS model is used to study the effects of laser incident angle and laser energy on the spatial characteristics of spectral intensity. The model is mainly based on fluid dynamics and SAHA equation. In the research, the best laser incidence angle, the best spectrum detection angle of the system under different parameters are obtained. The variation trend of the spectral intensity of laser plasma with the detection angle under different parameters is studied. The results show that 0° is the best incident angle for 1064 nm laser with different delay time and different delay conditions. When the incident angle is 0°, the excited plasma radiation has a stronger spectral signal at different detection angles. Corresponding to the incident angle of 0°, the optimal detection angles are ±41°, ±11° and ±12° at 100 ns, 500 ns and 1000 ns delay conditions, respectively. The simulation results also show that the signal intensity of the plasma radiation spectrum increases and then decreases at the optimal detection angle with the decrease of the absolute value of the detection angle. The experiments have verified the simulation results.
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