基于光轴正交的高分辨率激光探针仪实验研究

摘要

A designing scheme of the high-resolution and high-precision LIBS system was presented with an aiming at the problem of low resolution and poor accuracy. Using two mirrors with crossed optical axis and large numerical aper-ture lens,the LIBS instrument was obtained intergated coaxial-monitoring and coaxial-spectrum-acquisition system. Un-der the condition of coaxial monitoring system, the alignment accuracy of coaxial spectrum collection system in mi-cro-scale was ±9μm. Based on aluminum samples,the relationship between laser energy and resolution was researched, and the ultimate resolution was about 2.66μm at the input laser energy was 1.45μJ. The effective intensity spectrum was obtained at the same time.%针对激光探针分辨率低、精度差的问题，提出了一种高分辨率和高精度的激光探针系统。采用光轴正交的双反射镜和大数值孔径聚焦物镜，实现了集成同轴监测和同轴光谱采集系统的激光探针仪，在同轴监测系统作用下，同轴光谱采集系统的微区对准精度达±9μm；基于铝金属样品，实验研究了激光输入能量与分辨率的关系曲线，且在激光输入能量为1.45μJ时，在铝金属表面获得的极限分辨率为2.66μm，并能够采集到有效强度的光谱信号。