根据目标激光散射回波的基本特性和边缘跟踪概念, 设计并制作了一套单管调频连续波(FMCW)体制的相干式CO2激光雷达光学系统。这套系统的组合像差弥散斑直径约50 μm, 用0.18 mrad全发散角的细光束照射目标产生了较好的误差信号。激光束模式较好时, 系统接收到了7.8 km处房屋的后向散射信号, 经扫频窄带滤波后, 信号具有较高的信噪比, 此时激光器输出功率约为5 W。

An optical system is designed and fabricated on the basis of the target scattering characteristics and the edge tracking concept. This system is the optical head of a frequency modualated continous wave CO2 laser radar in which only a single mode CO2 laser is used. Using a collimator tube, the tested minimum light speckle on the focus plane is 50 μm in diameter. The acceptable error signals are engendered when a slender laser beam of 0.12 mrad angular divergence is directed on the diffuse target edge. The backscattered signals from building at 7.8 km are obtained with a fairly good SNR when the laser output is about 5W.