对反射层析激光雷达近场小系统成像进行了理论分析与模拟验证,当目标处于瑞利-索末菲衍射区域,到达目标的波前属于球面波衍射。根据奈奎斯特定律对球面波反射层析图像重建所需角度采样数,单投影采样点数约束条件进行了推导。引入了折线的方法,用于避免平方开方的距离运算,缩短图像重建时间。数值模拟表明此方法可以在降低计算量的前提下实现图像重建,随着探测距离的拉长,折线重建图像与参考图像相似度越来越高。 The theoretical analysis and simulation of the near-field small imaging system of the reflection laser lidar are carried out. When the target is in the Rayleigh-Sommerfeld diffraction region, the wavefront reaching the target belongs to the spherical wave diffraction. Based on Nyquist law, the number of angular samples needed for reconstruction of spherical wave reflection tomography and the constraint conditions of single projection sampling points are deduced. The introduction of the polyline method, used to avoid the square root of the distance calculation, shorten the image reconstruction time. Numerical simulation shows that this method can reduce the amount of computation under the premise of image reconstruction, with the detection of the extension of the distance, the polyline reconstruction image similarity with the reference image is getting higher and higher.