介质/金属膜空芯波导作为光谱吸收式气体传感的柔性吸收池,得到广泛关注。空芯波导具有损耗低、与光传输系统耦合稳定、抗外界干扰能力强和所需样品量微小等优点。利用傅里叶红外光谱仪(FTIR)和空芯波导搭建了气体传感系统,实验研究了各类波导对碱性气体、酸性气体以及有机溶剂挥发物等的耐久特性。通过对比波导注入腐蚀性气液体前后的损耗特性变化,评估波导的受损情况,讨论了劣化机理。系统总结了多种常用波导的适用传感波段和抗腐蚀特性,为波导式吸收池的工程应用提供了设计和制作参考。

Dielectric metallic hollow waveguides have attracted wide attention as flexible gas absorption cells for spectroscopic gas sensing. Advantages of the hollow waveguide include low loss, stable coupling with the optical transmission system, strong anti-interference ability, and a small sample volume. A spectroscopic gas sensing system was established using the Fourier infrared spectrometer (FTIR) and the flexible waveguide absorption cell. Durability characteristics of the waveguides were studied experimentally for various waveguides in alkaline gas, acidic gas, and volatile organic solvents. Loss properties of the hollow waveguide were measured before and after the corrosive treatment. Damage was evaluated and the degradation mechanism was discussed. The applicable sensing bands and corrosive environments of various commonly used waveguides were summarized systematically. Helpful choices are provided in the design and production for engineering application of the waveguide as the absorption cell.