Influence of horizontal damage size of grating ridge on the optical properties of multilayer dielectric gratings

Based on typical laser damage morphologies of multilayer dielectric gratings (MDGs), in this paper the influence of horizontal damage size of the grating ridge on optical properties of MDGs is analyzed by numerical calculations using the rigorous coupled wave analysis method. From simulation results, the optical performance of MDGs decreases with the increase in horizontal damage size of the grating ridge. But the maximum electric field value in the grating ridge and the multilayer enhances constantly with the increase in horizontal damage size, thus inducing further laser damage of MDGs. This paper provides the preliminary study for functional damage of MDGs.