公开(公告)号：US06664533B1

公开(公告)日：2003-12-16

申请号：US09488453

申请日：2000-01-20

申请人： Jan E. van der Laan ,  David E. Cooper ,  Russell E. Warren ,  Sylvie Carlisle

发明人： Jan E. van der Laan ,  David E. Cooper ,  Russell E. Warren ,  Sylvie Carlisle

IPC分类号： H01J4014

CPC分类号： G01N21/538 ,  G01J3/433 ,  G01N21/39 ,  G01N2021/1793

摘要： This specification discloses a method and apparatus for the mobile and remote detection of a gas, such as methane, in the atmosphere. The apparatus includes a TDL based Light Detection and Ranging (LIDAR) driven at carrier frequency lying within the absorption line of the gas. The apparatus also drives the TDL with a modulation frequency to generate upper and lower sidebands in the output of the TDL and with a low ramp frequency to sweep the output of the TDL across twice the width of the pressure-broadened absorption line of the gas, preferably the first overtone absorption line in the case of methane detection. The apparatus include reference and calibration cells or chambers, and includes a light collector and detectors to detect the quantity and modulation of the light that passes the reference or calibration cells and that is received by the apparatus after reflection back toward the apparatus from an uncooperative target. The apparatus further includes a signal processor that applies a derivative spectroscopy technique, such as frequency modulation spectroscopy or wavelength modulation spectroscopy, to determine the presence of the gas in the atmosphere.

摘要翻译： 本说明书公开了一种用于在大气中移动和远程检测诸如甲烷的气体的方法和装置。 该装置包括在位于气体的吸收线内的载波频率下驱动的基于TDL的光检测和测距（LIDAR）。 该装置还驱动具有调制频率的TDL，以在TDL的输出中产生上边带和下边带，并具有低斜坡频率，以扫过TDL的输出跨过气体的加压扩大吸收线的两倍宽度， 在甲烷检测的情况下，优选地是第一泛音吸收线。 该装置包括参考和校准单元或室，并且包括光收集器和检测器，用于检测通过参考或校准单元的光的数量和调制，并且在从不合作的目标反射回设备之后由设备接收 。 该装置还包括信号处理器，其应用衍生光谱技术，例如频率调制光谱或波长调制光谱，以确定气体在大气中的存在。

公开(公告)号：US4450356A

公开(公告)日：1984-05-22

申请号：US385490

申请日：1982-06-07

申请人： Edward R. Murray ,  Jan E. van der Laan ,  Arne Rosengreen ,  Robert L. Byer

发明人： Edward R. Murray ,  Jan E. van der Laan ,  Arne Rosengreen ,  Robert L. Byer

IPC分类号： G01N21/39

CPC分类号： G01N21/39

摘要： Gases in the atmosphere are detected remotely using a frequency-mixed CO.sub.2 laser beam formed by passing the beam from a first CO.sub.2 laser through a frequency doubler and then frequency-adding the output to the frequency from a second CO.sub.2 laser to obtain wavelengths in the 3 micron region. A first wavelength in this region, preselected for nonabsorption by the gases to be detected, is transmitted through the gases toward an object capable of reflecting the beam back. A second wavelength preselected as highly absorbed by the gases to be detected is then transmitted. The presence and quantity of the gases is then determined by the difference in the amount respectively absorbed at the two wavelengths.

摘要翻译： 使用通过将来自第一CO 2激光束的光束通过倍频器形成的频率混合的CO2激光束来远程检测大气中的气体，然后将输出频率加到来自第二CO 2激光器的频率以获得3 微米区域。 预先选择用于被被检测气体不吸收的该区域中的第一波长通过气体被传送到能够反射光束的物体。 然后传输预先被待检测气体高度吸收的第二波长。 然后通过分别在两个波长处吸收的量的差异来确定气体的存在和数量。