A vector algorithm for designing double off-axis diffractive lenses

A vector algorithm for designing two dimensions,finite aperture,aperiodic diffractive optical elements based on rigorous electromagnetic computation model the finite-difference time-domain method has been proposed.All aspects relating to the algorithm such as optimization process,the finite-difference time-domain method,and the diffractive integral,have been discussed.The algorithm can present rigorous design results with reasonable computational cost and good designing results.Two double off-axis diffractive lenses for normally incident TE mode have been designed to illustrate the algorithm.The algorithm is useful for the improvement of vector algorithm for designing diffractive optical elements and the applications of diffractive optical elements.