Gaussian profile laser intensification by nodular defects in mid-infrared high reflectance coatings

Electric field modeling of nodular defects is performed to investigate the interaction between defective multilayer coatings and Gaussian profile laser beam. Light-intensity is significantly enhanced as large as six times in areas adjacent to the defect boundary as well as within the defects. Different geometry of defects irradiated by a range of 0–45° incident laser is analyzed. Nodules with large but shallow seed or in the case of 45° oblique incidence tend to have the greatest enhancement effect.