Patent ID: 8780300
Filing Date: 2014-07-15
Classification: F21V,G02B,G02F

Abstract:
1. An optical member comprising: a planar Fresnel lens for deflecting and emitting incident light consisting of a plurality of luminous fluxes that have a directivity to a direction depending on an incident position of light, and focusing a principal-direction component of each luminous flux in the plurality of luminous fluxes toward a single observation point of an observer; and an element for restricting a direction of light rays that restricts the luminous fluxes emitted from the planar Fresnel lens to a direction parallel with the focused direction of the principal-direction component of each luminous flux emitted from the planar Fresnel lens, and further increases a directivity of the luminous fluxes, wherein the element for restricting the direction of light rays is a sheet in which a plurality of light absorptive areas and light transmissive areas are alternately arrayed, a boundary between the absorptive areas and the transmissive areas is sloped with respect to a direction perpendicular to the light-emitting surface so as to be parallel with the principal-direction component of the luminous fluxes emitted from the planar Fresnel lens, a direction of the light is restricted so that the light is emitted from a surface of the sheet along the principal-direction component of the luminous fluxes and that the emitted light is directed toward the single observation point.