Online monitoring of ethane traces in exhaled breath with a difference frequency generation spectrometer

被引：65

作者：

Halmer, D. ^{[1
]}

Thelen, S. ^{[1
]}

Hering, P. ^{[1
]}

Muertz, M. ^{[1
]}

机构：

[1] Univ Dusseldorf, Inst Lasermed, D-40225 Dusseldorf, Germany

来源：

APPLIED PHYSICS B-LASERS AND OPTICS | 2006年 / 85卷 / 2-3期

关键词：

D O I：

10.1007/s00340-006-2288-9

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

We report a transportable mid-infrared laser cavity leak-out spectrometer for online detection of trace gases. The laser spectrometer is based on continuous-wave difference-frequency generation in the wavelength region around 3 mu m. Sensitive spectroscopic trace gas monitoring was achieved using a high-finesse ring-down cavity. For difference-frequency generation, we use a periodically poled lithium niobate (PPLN) crystal, pumped by a Nd:YAG laser (signal wave) and a diode laser (pump wave) with a tapered amplifier. A maximum power of 280 mu W near lambda=3.3 mu m is achieved using a pump power of 180 mW at 807 nm, a signal power of 890 mW at 1064.46 nm, and a 50-mm-long PPLN crystal. The resulting system proved to be a unique tool with high sensitivity and specificity for rapid and precise breath testing. We demonstrate spectroscopic online monitoring of ethane traces in exhaled human breath with a precision of 270 parts per trillion (1 sigma) and a time resolution of 1 s.

引用

页码：437 / 443

页数：7