The results of computer simulation show that both the radius of disk and the depth of focal length decrease as increasing incidence wavelength, meanwhile, the intensity of disk is enhanced.

• 数值计算了圆形透镜的色散，结果表明：焦斑的半径和焦深随入射波长的变大而减小，光斑的强度随入射波长的变大而增强。