Fiber-distributed multi-channel open-path H_2S sensor based on tunable diode laser absorption spectroscopy

摘要

Tunable diode laser based gas detectors are now being used in a wide variety of applications for safety and environmental interest. A fiber-distributed multi-channel open-path H_2S sensor based on tunable diode laser absorption spectroscopy (TDLAS) is developed, the laser used is a telecommunication near infrared distributed feed-back (DFB) tunable diode laser, combining with wavelength modulation spectroscopy technology, a detection limit of 20 ppm-m is demonstrated. Multi-channel detection is achieved by combining optical fiber technique. An on-board reference cell provides on-line sensor calibration and almost maintenance-free operation. The sensor is suitable for large area field H_2S monitoring application.