Tow-Dimensional Micro-grating Formed by Polystyrene Spheres

We report a simple method to make two-dimensional plane gratings that can be used as splitters. In the self-assembly process, the colloidal spheres can form single layer square or triangular lattice on a flat surface and in our experiments the triangular lattice is a more common structure. As an incident beam passes through the triangular lattice, it can be split into seven sub-beams, among which six beams have the same density and scattering angle. This grating is not sensitive to the polarization direction of the incident light.