【摘要】 介绍了吸收型光纤气体传感器的工作原理,提出并分析了基于差分后谐波检测的光纤气体传感器的模型,并设计了传感器系统结构。利用参考光路与检测光路光强的差分消去基波分量,对差分后的信号再进行二次谐波检测得出气体浓度。使用该方法提高了系统检出二次谐波分量的能力,同时有效地提高了系统的分辨率。实验结果表明基于差分后谐波检测的光纤气体传感器具有良好的检测效果。更多还原

【Abstract】 Principle of absorption spectrum optical fiber gas sensor was introduced.Arithmetical model of optical fiber gas sensor based on difference and harmonic detection was presented and analyzed,and structure of the sensor was designed.Using the difference between referenced light intensity to metrical light intensity,we can counteract the fundamental wave component.Detecting 2nd harmonic of difference signal,we can obtain the gas concentration.By using this method,system’s ability of detecting 2nd harmonic component is improved,and system’s resolving power is increased too.Experimental results show that optical fiber gas sensor based on difference and harmonic detection has good detection effects.更多还原