摘要
腔衰荡光谱(CRDS)技术是一种高灵敏的激光吸收光谱技术,它实现的关键技术是在腔内激光强度达到一定值时,迅速将激光关断来探测光强的衰减信号。在激光与腔共振时,腔的反射信号迅速减小可以产生低电平来触发由TTL信号控制的声光调制器(AOM)关断激光,从而实现CRDS。在关断激光后用快速响应探测器对腔的衰荡信号进行探测,用Labview软件编程进行数据采集并编程拟合得到腔的衰荡时间,实验中测得空腔的衰荡时间为2.54μs。该方法简化了实验装置,可以应用到镜片反射率测量以及光谱分析应用等领域,具有较高的实用价值。
Cavity ring-down spectroscopy （CRDS） is a high sensitive absorption spectroscopy. The key technique is to cut off laser light sharply and detect the signal when the laser intensity inside the cavity reaches a certain value. When the laser frequency is resonant with the cavity, the CRDS can be realized utilizing the quickly decreased reflected light signal of cavity to trigger off the acousto-optic modulator controlled by TTL signal. As the laser light is interrupted, the ringdown signal can be detected with a fast respond detector.Labview is used to accomplish data acquisition and data fitting, and the fitting result of the ringdown time of the empty cavity is 2.54 us. The method is simple and valuable, and can be used in mirror reflectivity measurement and spectra analysis.
出处
《大气与环境光学学报》
CAS
2012年第6期458-462,共5页
Journal of Atmospheric and Environmental Optics
基金
国家重大科学研究计划资助(2012CB921603)
国家国际科技合作专项资助(2011DFA12490)
国家基金重点项目(10934004)
国家基金(60908019
60808009
61205216
61127017
61108030
61275213)
国家基金委创新研究群体(61121064)
山西省青年科学基金(2010021003-3)资助
关键词
腔衰荡光谱
声光调制器
反射光
衰荡时间
cavity ring-down spectroscopy
acousto-optic modulator
reflected light
ring-down time
