Lowering the reflection on curved flexible substrates over a broad wavelength range by the structure with Ag nanoparticles on SiO2 nanocolumns

Abstract A broadband antireflective structure with Ag nanoparticles on SiO2 nanocolumns for curved flexible substrates is presented. Experimental results show that the structure can lower effectively the light reflection on curved surfaces over a broad wavelength range. It is found that increasing incident angle leads to the blue-shift of position of the minimum light reflection due to the reduced travel distance of resonated electrons of Ag nanoparticles and the weakened mutual attraction between the resonated electrons in neighbouring Ag nanoparticles. The surfaces with smaller curvature radii have higher light reflection than those with larger curvature radii. The light reflection on a curved surface can be calculated through the weighted summation of the angle-dependent reflections on a flat surface, which agrees well with experimental results.