大气与环境光学学报, 2012, 7 (6): 458, 网络出版: 2012-11-29
基于腔反射光控制的腔衰荡光谱测量实验研究
Experimental Research of Cavity-Ring Down Spectroscopy Based on Control of Reflected Light of Cavity
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
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2.54 μs。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。
Abstract
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 μs. The method is simple and valuable, and can be used in mirror reflectivity measurement and spectra analysis.
李志新, 付小芳, 谭巍, 马维光, 董磊, 张雷, 尹王保, 贾锁堂. 基于腔反射光控制的腔衰荡光谱测量实验研究[J]. 大气与环境光学学报, 2012, 7(6): 458. LI Zhi-xin, FU Xiao-fang, TAN Wei, MA Wei-guang, DONG Lei, ZHANG Lei, YIN Wang-bao, JIA Suo-tang. Experimental Research of Cavity-Ring Down Spectroscopy Based on Control of Reflected Light of Cavity[J]. Journal of Atmospheric and Environmental Optics, 2012, 7(6): 458.