Du är här

Gas sensing by tunable multimode diode laser using correlation spectroscopy

Författare:
Publiceringsår: 2008
Språk: Engelska
Sidor: 671-676
Publikation/Tidskrift/Serie: APPLIED PHYSICS B-LASERS AND OPTICS
Volym: 93
Nummer: 2-3
Dokumenttyp: Artikel
Förlag: SPRINGER

Sammanfattning

A novel method to use multimode diode lasers for gas detection is demonstrated. The relationship between the intensity decay of partially absorbed multiple modes and the target gas concentration is presented. The gas concentration is retrieved by a linear-regression-based procedure applied on simultaneously recorded absorption signals in a dual-beam wavelength-modulation configuration. Signals of non-gas origin or disturbed by interfering gases are effectively eliminated by correlation analysis procedure. Light intensity fluctuations and wavelength shifts due to temperature drift are automatically compensated for. Several absorption signals can readily be obtained within a limited tuning range by overlapping the laser multimode chart with the target gas spectrum. This scheme was applied on the detection of trace acetylene mixed in ambient air, and a sensitivity of 3 ppm was achieved with a 48.5 cm path length. The trade-off between sensitivity and reliability for retrieving gas concentration by multiple absorption signals is also presented.

Disputation

Nyckelord

  • Physics and Astronomy
  • Ky
  • 65
  • 42
  • Fi
  • 62
  • Px
  • 55

Övrigt

Published
Yes
  • ISSN: 0946-2171

Box 117, 221 00 LUND
Telefon 046-222 00 00 (växel)
Telefax 046-222 47 20
lu [at] lu [dot] se

Fakturaadress: Box 188, 221 00 LUND
Organisationsnummer: 202100-3211
Om webbplatsen

LERU logo U21 logo