OPTICAL FILTER, OPTICAL DEVICE, ELECTRONIC DEVICE AND ANTI-REFLECTION COMPOSITE

摘要

There is provided an optical filter or an anti-reflection structure with lower reflection in comparison with the conventional ones by comprising a gradient refractive index thin film 12 with continuous, periodic refractive index change in the film thickness direction and a fine periodic structure 151 lowering reflection, wherein the refractive index of the gradient refractive index thin film 12 in its thickness direction on the substrate side changes so as to become close to that of the substrate, while on the fine periodic structure 111 changes so as to become close to that of the fine periodic structure 151. The optical filter can be used in an optical device or an electronic device display.