Firedamp remote optical fiber laser detection instrument for mine

The invention relates to a mine gas long-distance optical fiber laser detector, which comprises a light source and a first coupler and a second coupler which are connected with the light source, wherein, the first coupler is connected in series with the second coupler through a second optical fiber and connected with a reference gas chamber through a fourth optical fiber; light which are emitted from the reference gas chamber is connected with a third photo detector through a fifth optical fiber; one path of the second coupler is connected with a gas sensor probe through a third optical fiber; the other path of the second coupler is connected with a first photo detector through a sixth optical fiber; light which returns back from the gas sensor probe passes through the third optical fiber and the second coupler and then is connected with a second photo detector through a seventh optical fiber; the first photo detector, the second photo detector and the third photo detector are electrically connected with a data acquisition card, and electrical signals are then transmitted to a computer. The mine gas long-distance optical fiber laser detector is mainly used for coal mine gas detection.