Global control of colored moiré pattern in layered optical structures

Accurate description of visual effect of colored moire pattern caused by layered optical structures consisting of gratings and Fresnel lens is proposed in this work. The colored moire arising from the periodic and quasi-periodic structures is numerically simulated and experimentally verified. It is found that the visibility of moire pattern generated by refractive optical elements is related to not only the spatial structures of gratings but also the viewing angles. To effectively control the moire visibility, two constituting gratings are slightly separated. Such scheme is proved to be effective to globally eliminate moire pattern for displays containing refractive optical films with quasi-periodic structures.