公开(公告)号：WO2018064821A1

公开(公告)日：2018-04-12

申请号：PCT/CN2016/101521

申请日：2016-10-09

Applicant: SOUTH CHINA NORMAL UNIVERSITY

Inventor： SVANBERG, Sune ,  ZHAO, Guangyu ,  ZHOU, Bin

IPC: G01N21/31

CPC classification number: G01N21/39 ,  G01N21/552 ,  G01N2021/394 ,  G01N2201/0886

Abstract: A distributed optical fiber gas sensing system (100) based on evanescent field sensing, spatially resolved along the fiber (105, 200, 300) and obtained by employing differential absorption lidar techniques is described. The fiber (105, 200, 300) can be arranged in a plurality of ways, and could have a porous cladding (202) sensing fiber (105, 200, 300) as the sensing unit. The sensing fiber (105, 200, 300) has a solid core (201) to guide light and a porous cladding (202) to protect the fiber (105, 200, 300) from physical damage and to enlarge the interface of the evanescent field and the test gas. A pulsed or modulated laser (103), a 3-dB optical coupler (104) and a photomultiplier tube (PMT) (107) form a typical OTDR sensing system. The pulse generator (102) is to control the pulse width, period, duty cycle of the pulsed laser (103). The data acquisition card (106) is to record the amplitude of the reflected light detected by the PMT (107). The controller (101) which usually is a computer is for signal recording and system synchronizing.

Abstract translation: 描述了基于渐逝场感测的分布式光纤气体传感系统（100），其沿光纤（105,200,300）空间分辨并通过采用差分吸收激光雷达技术获得。 纤维（105,200,300）可以以多种方式布置，并且可以具有感测纤维（105,200,300）作为感测单元的多孔包壳（202）。 传感光纤（105,200,300）具有引导光的实芯（201）和多孔包层（202），以保护光纤（105,200,300）免受物理损伤并扩大消逝场的界面 和测试气体。 脉冲或调制激光器（103），3-dB光耦合器（104）和光电倍增管（PMT）（107）形成典型的OTDR传感系统。 脉冲发生器（102）用于控制脉冲激光器（103）的脉冲宽度，周期，占空比。 数据采集​​卡（106）记录由PMT（107）检测到的反射光的振幅。 通常是计算机的控制器（101）用于信号记录和系统同步。