光纤气体传感器的研究

基于气体在吸收峰波长下对光的吸收随浓度变化的机理，研制一种光纤式气全监测仪。根据被测气体的吸收峰对应的波长选择ＬＥＤ作为光源。采用不同频率的光源驱劝电路实现多种气体浓度的产时检测。为保证测量精度，信号处理采用相敏以及测量信号与参考信号比值技术。对甲烷和乙炔气体浓度的检测实验表明，系统具有一定的检测灵敏度和精度。仪器和系统不驻适于甲烷和乙炔气体浓度的检测，稍加改变结构参数，也可测量其它气体的浓度。

Study on Gas Sensor with Optical Fiber

The gas monitor with optical fiber is developed bas-ed on the Principle that the absorption light changes with gasintensity under absorptive peak wavelength. The LED ofdriving light source is selected by the absorptive peak wavel-ength of measured gas. The light source driving circuit withthe different frequency is used to detect the varied gas in realtime. The techniques of phase-sensitive detected and ratio be-tween measured signal and reference signal is used to ensuremeasurement accuracy. The experiment result of methane andacetylene intensity indicates that the system has higher detec-ted sensitivity and detect accuracy. The intuent and systemis not only used to detect the methane and acetylene intensity,but also to detect other gas intensity under a little structure par-ameter change.