Screen, optical film, and method of manufacturing an optical film
There is provided a screen, which, with a simple configuration, is capable of effectively utilizing light projected thereon and realizing an even luminance distribution on the screen. This screen has a diffusion layer whose diffusion characteristic expressed as a luminance distribution with respect to a scattering angle of incident light incident at an angle of 0° is varied such that the peak position of the luminance distribution is shifted towards a greater value of scattering angle in the direction of the central portion of the screen the greater the distance from the central portion of the screen is. The present invention also provides an optical film suitable for use in such a screen, and a manufacturing method therefor.
1. A screen for displaying an image by having image light projected thereonto, comprising:
a diffusion layer whose diffusion characteristics expressed as a luminance distribution with respect to a scattering angle of incident light incident thereon at an incident angle of 0° vary in such a manner that the peak position of the luminance distribution is shifted towards a greater value of scattering angle in the direction of a central portion of said screen as the distance from said central portion of said screen increases; and
wherein said diffusion layer has a plurality of convex or concave parts provided on a surface thereof for scattering image light, and wherein a gradient of a slope, which is closer to said central portion of said screen, of each of said convex or concave parts becomes larger as the distance between said convex or concave parts and said central portion of said screen increases,
wherein the size of each of said convex or concave parts and the interval therebetween are smaller than the size of a pixel,
further comprising a reflective layer for reflecting image light; and
wherein said reflective layer has a highly reflective property for light of a specific wavelength range corresponding to image light, and wherein said reflective layer has one of a highly transmissive property and a highly absorptive property for at least light in the visible wavelength range outside said specific wavelength range.
2. The screen according to claim 1 , wherein said reflective layer comprises a multilayer film in which high refractive index layers and low refractive index layers, whose refractive index is lower than that of said high refractive index layers, are alternately stacked.
3. The screen according to claim 1 , further comprising an absorption layer for absorbing light transmitted through said reflective layer.