用Lie代数方法分析了相对论强流脉冲束在轴对称静电透镜中的非线性传输,得到粒子在6维相空间(x,x’,y,y’,τ,pτ)中的2级近似轨迹.在分析中,把静电透镜的场作用区分成若干小段,每个小段看作匀加速段,而每个分点看作薄透镜,依次施加Lie变换,就得到轨迹的各级近似.这里,假定粒子在相空间中为K-V分布. The nonlinear propagation of the relativistic intense pulsed beam in an axisymmetric electrostatic lens was analyzed by Lie algebra method, and the second-order approximate trajectory of the particle in the 6-dimensional phase space (x, x ’, y, y’, τ, pτ) In the analysis, the field effect of the electrostatic lens is divided into several small segments, each of which is regarded as a uniform acceleration segment, and each of the points is regarded as a thin lens, and successive Lie transformations are applied to obtain approximations at all levels of the trajectory Here, It is assumed that the particles are KV distributions in the phase space.