散射增强型光声光谱技术机理及其应用研究

痕量气体检测技术在电力系统故障特征气体分析、医疗领域呼吸气检测和工业有害气体排放监测等应用中发挥重要的作用。为了进一步提高痕量气体在线检测的灵敏度，急需对光声光谱技术进行机理和结构上的深入探索和创新。本项目提出新的散射增强型光声光谱技术，利用多孔散射材料可以显著提高光程的特点，实现痕量气体的高灵敏度测量。项目以散射增强型光声光谱技术的机理研究为核心，重点研究光声信号在多孔散射材料中的激发和传输机制；通过有限元方法分析光声池和光纤声波传感器的声学特性，完成集成化气体传感探头结构的设计；采用半导体激光器级联光纤放大器作为激发光源，结合多孔散射材料，建立新型的散射增强型光声光谱痕量气体检测系统。该研究方案有望为光声光谱技术提供创新的理论支撑，为高灵敏度痕量气体检测提供一种更优化的解决方案。

Trace gas detection plays important roles in the fields of characteristic gases analysis of electrical installation, breathing gases detection of medical diagnosis and noxious gas emission monitoring of industrial production. To improve the sensitivity of online trace gas detection, it is urgent to explore and innovate the mechanism and structure of photoacoustic (PA) spectroscopy (PAS). A novel scattering enhanced photoacoustic spectroscopy (SEPAS) based on porous scattering material is proposed in this project. The project focuses on the principle of the SEPAS and lays a strong emphasis on how the PA signals generate and transmit in the porous scattering material. Meanwhile, integrated gas detectors are designed on the basis of simulation analysis by finite element method. Finally, a novel SEPAS based high-sensitivity trace gas detection system is fabricated. A distributed feedback (DFB) laser cascaded with an erbium-doped fiber amplifier (EDFA) is used as the PA excitation source in this system. The proposed SEPAS will provide a better solution for high sensitive trace gas detection.