Abstract
An external-cavity tunable diode laser operating at near-IR region is used to detect acetylene with laser absorption spectroscopy. Quantitative measurement of gas concentration is obtained by applying low-frequency wavelength modulation to the tunable laser and by phase-sensitive-detection of the fundamental and second-harmonic signals using a lock-in amplifier. A single-sensor and a time-division multiplexed two-sensor system have been implemented and experimentally tested. The sensor systems use single path 25 mm absorption cells and have demonstrated sensitivity of 75 ppm for the single sensor system and 182 ppm for the multiplexed two-sensor system.
| Original language | English |
|---|---|
| Pages (from-to) | 124-133 |
| Number of pages | 10 |
| Journal | Proceedings of SPIE - The International Society for Optical Engineering |
| Volume | 3852 |
| Publication status | Published - Dec 1999 |
| Event | Proceedings of the 1999 Harsh Environment Sensors II - Boston, MA, USA Duration: 19 Sept 1999 → 19 Sept 1999 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering