A vector angular-spectrum iterative algorithm for the design of diffractive optical elements to produce uniform illumination is described. In the algorithm, the variation of beam polarization is related to a unit wave vector and a random mixture of intensity is used for super-Gaussian beam shaping [corrected]. The simulated results show that approximately 95.3% of the incident energy has converged into the desired region. The greatest profile error and the mean-square error of intensity fitted to the corresponding parameters of the 100th-power super-Gaussian function are approximately 8 x 10(-4) and 3.5 x 10(-3), respectively.