利用氮化镓二极管激光器和二极管泵浦钇铝石榴石激光器通过激光诱导荧光对大气中的二氧化氮进行痕量检测。

Trace detection of atmospheric NO2 by laser-induced fluorescence using a GaN diode laser and a diode-pumped YAG laser.

作者信息

Taketani Fumikazu, Kawai Megumi, Takahashi Kenshi, Matsumi Yutaka

机构信息

Solar-Terrestrial Environment Laboratory, Graduate School of Science, Nagoya University, Honohara, Toyokawa, Aichi, Japan.

出版信息

Appl Opt. 2007 Feb 20;46(6):907-15. doi: 10.1364/ao.46.000907.

DOI:10.1364/ao.46.000907

PMID:17279136

Abstract

We report on the development of a highly sensitive detection system for measuring atmospheric NO(2) by means of a laser-induced fluorescence (LIF) technique at 473 nm using a diode-pumped Nd:YAG laser. A GaN-based laser diode emitting at 410 nm is also used as an alternative fluorescence-excitation source. For laboratory calibrations, standard NO(2) gas is diluted with synthetic air and is introduced into a fluorescence-detection cell. The NO(2) LIF signal is detected by a photomultiplier tube and processed by a photon-counting method. The minimum detectable limits of the NO(2) instrument developed have been estimated to be 0.14 ppbv and 0.39 ppbv (parts per billion, 10(-9), by volume) in 60 s integration time (signal-to-noise ratio of 2) for 473 and 410 nm excitation systems, respectively. Practical performance of the instrument has been demonstrated by the 24 hour continuous measurements of ambient NO(2) in a suburban area.

摘要

我们报告了一种高灵敏度检测系统的研发情况，该系统利用激光诱导荧光（LIF）技术，借助二极管泵浦的Nd:YAG激光器，在473纳米波长下测量大气中的二氧化氮（NO₂）。一种发射波长为410纳米的基于氮化镓（GaN）的激光二极管也被用作替代的荧光激发源。在实验室校准中，标准NO₂气体用合成空气稀释后被引入荧光检测池。NO₂的LIF信号由光电倍增管检测，并通过光子计数法进行处理。对于473纳米和410纳米激发系统，在60秒积分时间（信噪比为2）内，所研发的NO₂仪器的最低检测限分别估计为0.14 ppbv和0.39 ppbv（十亿分比，体积比为10⁻⁹）。该仪器的实际性能已通过在郊区对环境NO₂进行24小时连续测量得到了验证。