基于光电倍增管的时间分辨激光诱导击穿光谱分析系统

The Time Resolved Laser Induced Breakdown Spectroscopy System Based on PMT

基于光电倍增管（PMT）设计了光谱检测系统,采用多路模拟开关控制积分电路与激光脉冲同步光谱采集,可以精确控制延时时间和积分时间,实现了时间分辨的光谱采集。通过应用于激光诱导击穿光谱（LIBS）系统,对碳钢中C、Si、Mn、Cr、Ni、Cu等元素采用时间分辨和连续积分两种模式采集光谱进行对比分析,可以有效地提升信噪比,并降低检出限,这为LIBS技术应用于微量元素分析提供了一种低成本实现方法,也为LIBS在各领域的推广应用提供了更多选择。

The paper designed a spectral detection system based on photomultiplier tube（ PMT）. The multi-channel analog switch is used to control the integrated circuit and laser pulse synchronous spectrum acquisition. The delay time and integration time can be precisely controlled,to achieve the time-resolved spectral acquisition. Through the application of laser induced breakdown spectroscopy（ LIBS） system,the spectra of C,Si,Mn,Cr,Ni,Cu and other elements in carbon steel using time-resolved and continuous-integral of two models to collect the spectrum of are comparatively analyzed. The results show that the signal to noise ratio can be improved and the detection limit can be reduced,which not only provides a low-cost implementation method for the LIBS technology used in trace element analysis,but also provide more choices for the promotion and application of LIBS in various fields.