激光诱导荧光水质监测系统的研制

Development of the laser induced fluorescence detecting system for water quality monitoring

提出以Nd:YAG激光器的三倍频355nm波长激光为激发光源,以单个光电倍增管(PMT)为探测器,以水体污染监测为目的的激光诱导荧光系统的研制。采用光电倍增管高速双脉冲门控与单次脉冲触发数据采样相结合新技术,有效减少了户外环境下背景光的影响,提高了系统的测量精确度。试验结果表明,该系统能接收水体表面受激发射的荧光信号,探测到的荧光信号经信号处理后与水体受污染程度有良好的相关性。

Fluorescence Detecting system for Water quality monitoring based on laser induced fluorescence （LIF） is described in this paper, which is using the 355nm third harmonic Nd： YAG as the excite source and photomultiplier （PMT） as the detector. In order to reduce the background light disturbed, high-speed double pulse trigger PMT in a time data acquisition as an originality innovation is proposed. After combined with background correction and data processing, a better measured resulted is showed in the experiments. There is a good correlation between pollution concentration and the normalization fluorescence intensity of ultraviolet laser induced fluorescence. Therefore this system is high sensitivity and good correlation with pollution concentration for in vivo monitoring polluted water column.