用非平衡统计计算了无界金属圆柱的介电函数结果表明，电子非弹性散射的柱体表面会影响金属的内禀介电函数当往体半径减小到可与电子的平均自由程相比拟时，介电函数逐渐偏离块体值而依赖于局城位置．除了半径远小于电子平均自由程的区域，介电函数的位置依赖关系十分复杂，尺寸效应可能使介电函数实部和虚部的绝对值都增大；尺寸效应显著地增加介电常数虚部与实部的相对值大小．在高频区域，尺寸效应使得介电函数具有振荡形式的径向分布 Calculating the dielectric function of unbounded metal cylinder with non-equilibrium statistics shows that the surface of electron inelastic scattering affects the intrinsic dielectric function of metal. When the radius of the electron body decreases to be comparable to the mean free path of electrons , The dielectric function gradually deviates from the block value and depends on the location of the local city. Except for areas with a radius much smaller than the mean free path of electrons, the location dependence of the dielectric function is very complicated. The size effect may increase the absolute value of the real and imaginary parts of the dielectric function. The size effect significantly increases the imaginary part of the dielectric constant And the real part of the relative size. In the high frequency region, the size effect causes the dielectric function to have a radial distribution of oscillation