Regional iterative optimization algorithm to reduce error caused by DOE binarization

To reduce the manufacturing cost and the manufacturing time, the continuous phase profile of a diffractive optical element is usually quantized into two levels, which causes the degradation of optic performance. Based on the deep analysis on the existing binarization algorithms, the paper proposes an algorithm based on regional iterative optimization. The simulation results show that the proposed algorithm can achieve improvements on mean square error, average amplitude in the output area, and nonuniformity. The phase patterns created by different algorithms are fabricated on polyethylene glycol terephthalate substrates by maskless lithography technology. The image reconstructed by the proposed algorithm exhibits higher intensity, more accurate shape, and higher uniformity.