一种二次镀银光纤光栅气敏传感器

A double-plating silver FBG gas sensor

为了更加有效地实时检测井下硫化氢(H2S)气体,提出一种在光纤Bragg光栅(FBG)上二次涂镀银(Ag)膜的光纤气敏传感器。一方面,采用二次镀Ag的制备方法增加Ag膜的均匀性,提高气敏元件的灵敏度;另一方面,采用特殊的油气分离、流线型设计,保证了H2S气体与气敏元件的有效接触,实现井下低浓度气体的实时检测。根据实验,当镀Ag的FBG气敏元件置于H2S气体中时,传入光纤的倏逝波能量减小,反射光谱的峰值功率下降2.0dBm。

In order to detect hydrogen sulfide （H2S） gas more effectively, a double-plating silver fiber Bragg grating （FBG） gas sensor is proposed. On the one hand,the double-plating silver is adopted to in- crease the uniformity of the silver film and improve the sensitivity of gas sensor. On the other hand,the sensor which is designed to achieve the separation of oil and gas is used to ensure the effective contact between the H2S gas and the gas sensor, and to complete real-time detection of low concentration gas in underground mine. According to the experiment of double-plating silver FBG gas sensor, the relationship between the H2S gas concentration and absorption spectrum is obtained. Results indicate that the energy of evanescent wave decreases and the peak power of back reflection spectrum drops by 2. 0 dBm.