Patent ID: 8283857
Filing Date: 2012-10-09
Classification: H01J,H01L

Abstract:
1. An image display apparatus comprising: a luminescent layer; an excitation source which excites the luminescent layer; a front layer which obtains display light by transmitting light generated by the luminescent layer excited by the excitation source; and a periodic structure provided between the front layer and the luminescent layer, the periodic structure including a periodic refractive index distribution in a surface parallel to the front layer, wherein the periodic structure is configured to attenuate reflection of outside light incident into the front layer, wherein the periodic structure satisfies a relation of a following expression (1) and a periodic interval of the periodic structure is equal to or greater than 1 μm and equal to or less than 3 μm, wherein said expression (1) is given by, where N N wherein the periodic structure has a two-dimensional periodic refractive index distribution in the surface parallel to the front layer, wherein the periodic structure has a refractive index distribution in a triangular lattice shape, a square lattice shape, or a rectangular lattice shape, and wherein the periodic structure has a structure in which in a layer comprised of a first medium, cylindrical structures comprised of a second medium different from the first medium are periodically arranged and has, the structure satisfying a relation of a following expression (7), wherein said expression (7) is given by, where