论文部分内容阅读
气体传感理论和实验研究已成为当今光纤传感领域的热点之一。波长调制法和有源内腔法是提高气体传感灵敏度的两种有效方式。结合上述两种气体传感方法,构建一个基于波长调制技术的内腔式气体传感系统。讨论气体吸收光谱二次谐波分量与气体浓度之间的函数关系,从理论和实验两方面确定系统的最佳参数。利用提取多条吸收谱线的二次谐波分量,采用平均算法进一步提高系统灵敏度,进行乙炔气体传感的灵敏度可达7.5×10-5。以光纤光栅作为波长参考,建立系统的波长-电压响应曲线,进而检测气体的吸收波长值。进行乙炔气体传感时吸收波长检测的绝对误差不超过0.445 nm。
Gas sensing theory and experimental research have become one of the hot topics in the field of optical fiber sensing. Wavelength modulation method and active cavity method are two effective ways to improve the sensitivity of gas sensing. Combining the above two gas sensing methods, a cavity-based gas sensing system based on wavelength modulation technology is constructed. Discuss the gas absorption spectrum of the second harmonic component and the gas concentration as a function of the relationship between the theoretical and experimental aspects to determine the optimal parameters of the system. By extracting the second harmonic components of multiple absorption lines, the average algorithm is used to further improve the sensitivity of the system, and the sensitivities of acetylene gas sensing can reach 7.5 × 10 -5. With the FBG as the reference wavelength, the wavelength-voltage response curve of the system was established, and then the absorption wavelength of the gas was detected. The absolute error of absorption wavelength detection for acetylene gas sensing does not exceed 0.445 nm.