Differential Absorption LIDAR Imaging

基于激光的测量越来越多地用于提取包括浓度的气体参数。如果目标气体存在，它将吸收激光功率，这种吸收与气体的浓度成比例。除了测量吸收，还可以通过检查激光脉冲行进所需的时间来测量气体的距离，这被称为光探测和测距（LIDAR）。这可以通过使两个激光源以紧密间隔的波长操作来扩展，一个波长对目标气体具有高吸收性，而另一个波长则不是。通过比较两个波长的检测值，可以确定浓度，这被称为差分吸收激光雷达（DIAL）。本工作将开发一个用于气体浓度和范围测量的台架安装DIAL系统。

Laser based measurements are increasing being used to extract gas parameters including concentration. If the target gas is present it will absorb laser power, this absorption is proportionally to the concentration of the gas. As well as measuring absorption, range to gas can also be measured by examining the time it takes for the laser pulses to travel, this is known as light detection and ranging (LIDAR). This can be extended by having two laser sources operating at closely spaced wavelengths, one wavelength is highly absorbent to the target gas the other is not. By comparing the detected values for both wavelengths the concentration can be determined, this is known as differential absorption LIDAR (DIAL). This work will develop a bench mounted DIAL system for gas concentration and range measurements.