I4.4 - Preconcentrator Module for the Implementation in Optical Gas Measurement Systems
- Event
- SENSOR+TEST Conferences 2009
2009-05-26 - 2009-05-28
Congress Center Nürnberg - Band
- Proceedings OPTO 2009 & IRS² 2009
- Chapter
- IRS² 4 - Gas Analysis
- Author(s)
- J. Hildenbrand, A. Eberhardt, C. Peter, J. Woellenstein - Fraunhofer-Institute for Physical Measurement Techniques, Freiburg, Germany, J. Korvink - University of Freiburg, Freiburg, Germany
- Pages
- 269 - 274
- DOI
- 10.5162/irs09/i4.4
- ISBN
- 978-3-9810993-6-2
- Price
- free
Abstract
Fabrication process monitoring in industrial applications, safety and environmental monitoring e.g. for the determination of toxic gases are typical fields of applications in modem gas measurement tasks. In the lower price segment solid state devices like metal oxide based gas sensors are typically used. These sensors are very sensitive but they show high cross-sensitivities and a significant signal drift. Optical techniques distinguish by the compensation of these two disadvantages and it is still possible to get inexpensive absorption spectroscopic systems for e.g. C2H4. In general these systems are based on thermal IR-sources, a simple absorption cell without optical elements and a detector. The decreasing of the detection limit is mainly reached by increasing of the optical path. We present a new approach to improve the sensitivity of these systems based on a Reconcentrating unit mounted to absorption cell.