A CO detection system based on double fiber bragg gratings

CO is the main component of mine gas. It is flammable and explosive. It is very important to realize the real-time detection of CO gas. It concentrates to the safety of mining industry and personal safety. In this paper, a double optical fiber sensing system based on a set of differential absorption technique is designed according to the CO molecular spectral absorption characteristics. The light source is LED. Reentrant type absorption cell is used as the gas chamber. The wavelength modulation and narrow beam are obtained by the fiber grating and photoelectric diode. The differential absorption detection is realized by the application of fiber Bragg grating narrowband filter characteristics and the double optical path. It is shown by the experiment that the system has high feasibility and reliability. The high sensitive detection of CO gas can be readily achieved.