Laser Diode Gas Spectroscopy
نویسنده
چکیده
The use of laser sources for optical spectroscopy experimentation is a well-established, cross-disciplinary field with an enormous number of applications in research areas as broad as Physics, Chemistry or Biology (Demtröder, 1996). The high optical intensity achieved with these types of sources, along with the extraordinary monochromaticity of their optical output, has a huge impact in spectroscopy research. In particular, the application to gas sensing in weak absorption spectral regions significantly benefits from the specific properties of laser. Gas species exhibit well-defined, complex spectral absorption structures that require the utilisation of tuneable, high resolution and spectrally narrow sources to be resolved. Such requirements are fulfilled by several types of Tuneable Diode Lasers (TDL’s) readily available from the optical telecommunication industry, where much work was done during the last decades to develop and improve the characteristics of these laser devices. Further technology development and intensive research has lead to TDL’s of high optical power and narrow emission linewidth to be routinely available for research groups across the world, thus opening the possibility for investigation of gas absorption processes of increasing complexity and very narrow spectral scales. In addition, advances in manufacturing technology have enabled the design and fabrication of new photonic microstructures in parallel to the development of laser sources. The combination of both factors has thus multiplied the possibilities for challenging gas-sensing research, which in turn reveals new fundamental characteristics of gaseous systems whose study requires more and more stable, narrow linewidth and powerful laser sources.
منابع مشابه
Field detection of CO and CH4 by NIR 2f modulation laser spectroscopy
A novel compact fiber-coupled NIR system based on a DFB diode laser source is employed as a portable and sensitive gas sensor for trace detection of combustion pollutant molecules. We demonstrate the performance of such an NIR gas sensor by tracing the absorption lines of CO and CH4 using 2f-WMS technique at moderate temperature of T ~ 600°C in the recuperator channel of an industrial furnace...
متن کاملProposal Daniel J . Evans Build - Up Cavity Coupled to a Laser Diode Center of Excellence for Raman Technology
The proposed thesis is to build a power build-up cavity pumped by a laser diode. In Raman spectroscopy there is a need for high power laser diode sources to be used in Raman gas monitoring applications. A high power laser source will allow the development of compact and low cost systems for use in any gas monitoring application where detection into the ppb is necessary. Gas detection can be acc...
متن کاملA review of recent advances in semiconductor laser based gas monitors
When first tunable diode lasers were developed in the mid-1960s they found immediate application as much needed tunable sources for high-resolution laser absorption spectroscopy commonly referred to as TDLAS (tunable diode laser absorption spectroscopy). Substantial improvements in sensitivity and detection speed have been achieved since then and an increasing number of laser based gas monitori...
متن کاملSEMICONDUCTOR LASER BASED TRACE GAS SENSOR TECHNOLOGY: RECENT ADVANCES AND APPLICATIONS Laser Based Trace Gas Sensor Technology
Recent advances in the development of sensors based on infrared diode and quantum cascade lasers for the detection of trace gas species is reported. Several examples of applications in environmental and industrial process monitoring as well as in medical diagnostics using quartz enhanced photoacoustic spectroscopy and laser absorption spectroscopy will be described.
متن کامل