An optical fiber gas sensor mainly consists of two parts: optical part and detection circuit. In the debugging for the detection circuit, the optical part usually serves as a signal source. However, in the debugging condition, the optical part can be easily influenced by many factors, such as the fluctuation of ambient temperature or driving current resulting in instability of the wavelength and intensity for the laser; for dual-beam sensor, the different bends and stresses of the optical fiber will lead to the fluctuation of the intensity and phase; the intensity noise from the collimator, coupler, and other optical devices in the system will also result in the impurity of the optical part based signal source. In order to dramatically improve the debugging efficiency of the detection circuit and shorten the period of research and development, this paper describes an analog signal source, consisting of a single chip microcomputer (SCM), an amplifier circuit, and a voltage-to-current conversion circuit. It can be used to realize the rapid debugging detection circuit of the optical fiber gas sensor instead of optical part based signal source. This analog signal source performs well with many other advantages, such as the simple operation, small size, and light weight.

基于气体近红外选择性吸收理论和Beer-Lambert定律，研究了硫化氢气体的拉曼散射特性，同时采用宽带光源光谱吸收检测技术对H2S气体进行检测。将自聚焦透镜作为光纤准直透镜和聚焦透镜，并将其应用于透射型气室。同时，提出了在透射式气室中将多对自聚焦透镜组串联使用以增加吸收光程的方法，该方法可以明显提高气室的检测灵敏度。通过分析实验测得的H2S吸收曲线，得到系统的灵敏度为3.672×10-4 μW/(μL/L)，分辨率为122.5 μL/L。

The authors review their recent advances in the development of optical fiber Bragg grating (FBG) sensor technologies. After a brief review of the fiber grating sensors, several newly developed FBG sensors are described. With the continuous development of fiber materials, microstructures and post-processing technologies, FBG sensors are still creative after the first demonstration of permanent gratings thirty years ago.

提出了一种基于计算机的光纤气体传感器谐波检测的实验室解调方案.系统采用分布反馈式半导体激光器和数据采集卡,并利用所设计的解调软件进行信号解调,实现了气体浓度的谐波检测,并能实时显示采集波形及分析波形.

论述了光声光谱信号的产生。提出用光纤相位传感器代替传统的微音器检测光声信号,讨论了光纤中光波的相位变化与光声信号的关系。设计了光学长程结构,有效增加了对光功率的吸收。用染料激光器作光源对SO2气体浓度进行测量。实验表明,最低检测灵敏度可达1.2×10-10。 由于采用光谱技术与光纤技术相结合,使研制的传感器具有较高的灵敏度,信号的传输通道具有强的抗电磁干扰及防燃防爆能力。气体探头体积小,响应速度较快。信号处理电路具有较强的抑制噪声干扰能力。该传感器及其系统在灵敏度、精度、响应时间等性能指标上达到了检测气体含量要求。