Design of Varied Line Spacing Holographic Gratings Based on Cascade Evolutionary Strategy

In the optimal design of varied line spacing (VLS) holographic grating, it is expected to locate multiple alternative solutions in the complicated objective landscape. A cascade evolutionary strategy (CES) algorithm is proposed to solve the multimodal optimization problem. The inner ES works as a local search operator to exploit the niches, while the outer ES works as a regulator to adjust the parameters of inner ES, and introduces competition between the niches. Optimization results of both test function and practical design prove the efficiency and usefulness of CES