Electrically switchable two-dimensional photonic crystals made of polymer-dispersed liquid crystals based on the Talbot self-imaging effect

Electrically switchable two-dimensional photonic crystals were demonstrated using polymer-dispersed liquid crystal materials based on the Talbot self-imaging effect of a single photomask. With the photomask subjected to a collimated Ar+ laser beam operating at 488 nm, a three-dimensional spatial light intensity pattern was created due to the Talbot self-imaging effect. The spatial light intensity pattern was then recorded inside a cell filled with the liquid crystal/prepolymer mixture to create photonic crystal structures. The surface morphology of the photonic crystals was examined by an atomic force microscopy. It showed square structures with a lattice constant of similar to 0.9 A mu m. The diffraction and electro-optical properties were also presented. This approach shows a simple and fast fabrication.