基于闭环控制的太赫兹时域光谱快速采集  

Terahertz Time-Domain Spectroscopy Rapid Data Acquisition Based on Closed-Loop Control

作　　者：黄战华[1] 胡子晓 何明霞[1] 龙宁波[1] 刘洋[1] 

机构地区：[1]天津大学光电信息技术教育部重点实验室,天津300072

出　　处：《激光与光电子学进展》2015年第4期44-51,共8页Laser & Optoelectronics Progress

基　　金：科技部重大仪器专项(2011YQ150021)

摘　　要：太赫兹时域光谱(THz-TDS)技术作为一种快速发展的新型光谱分析方法在诸多领域备受关注。目前传统THz-TDS检测时间慢,数据采集量低。为了提高THz-TDS检测速度与精度,根据等效采样原理,设计了一种基于闭环控制的快速THz-TDS数据采集系统。该系统可进行快速连续扫描采集,步进扫描时通过光学延迟线的信号反馈来实时获取其位置信息,完成自动化快速扫描。通过每步连续采集多个数据点来提高单步采集的准确性。结果表明,该系统充分利用了光学延迟线的硬件性能,可实现最高500 k Hz的数据采集,步长5 mm时单步连续采集1000个数据时间仅为86.34 ms,系统能够对太赫兹时域脉冲信号进行高精度自动化快速采集。As a new spectral analysis method, terahertz time-domain spectroscopy （THz-TDS） is rapidly developing in many fields. Conventional THz-TDS systems have a long detection time and a small amount of collected data. To improve THz-TDS system＇s detection speed and accuracy, a rapid THz-TDS data acquisition and control system based on closed-loop control are presented. The system can perform continuous scanning and data collection with a high speed. When performing step scanning, it can get real-time location information of the optical delay line by the delay line＇s feedback signal, and thus can complete automatic scanning rapidly. By acquiring multiple data continuously in a single step, the accuracy of acquisition in every step is improved. Results show that the system can take full advantage of the optical delay line to achieve a highest data acquisition speed of 500 kHz. When the step length is 5 μm, the time of continuous acquisition of 1000 data is only 86.34 ms, which means the system can perform automatic and rapid acquisition of terahertz time-domain pulse signal with high precision.

关 键 词：光谱学 太赫兹时域光谱 数据采集 闭环控制 连续扫描 步进扫描 

分 类 号：O436[机械工程—光学工程]