Abstract: In an optical sheet 10 having a prism surface 16 formed by providing unit prisms 14 on the upper surface of a transparent base material 12, a coating layer 18 is provided on the reverse surface of the transparent base material opposite to the prism surface 16, spherical beads 20 are arranged projecting from the surface of the coating layer 18 by 1 to 10 .mu.m in height, and the coating layer 18 is brought into contact with the flat and smooth surface 22A of the light-transmissive material 22 through the spherical beads 20 which are put between them. The spherical beads are 1 .mu.m or less in half bandwidth of the distribution of particle diameters and are made uniform in height projecting from the coating layer 18.

Abstract: A light diffusing film is produced by preparing a paint by adding a light transmissive diffusing material comprising resin beads to a light transmissive resin, and coating the paint on one or both of the surfaces of transparent film substrate made of TAC, to produce a light diffusing layer. In the light diffusing film, the haze value on the surface of light diffusing layer is three or more, the difference between the haze value along the normal and that along the lines .+-.60.degree. apart from the normal is four or less, and the surface is practically smooth whose roughness is so adjusted as to give a surface roughness Ra of Ra.ltoreq.0.2 .mu.m. Application of such a light diffusing film onto a display panel inhibits scattering reflection which would otherwise cause the display to be whitish, reduces the variation of haze values which vary depending on the viewed angle, and thus improves display quality.

Abstract: In an optical sheet 10 having a prism surface 16 formed by providing unit prisms 14 on the upper surface of a transparent base material 12, a coating layer 18 is provided on the reverse surface of the transparent base material opposite to the prism surface 16, spherical beads 20 are arranged projecting from the surface of the coating layer 18 by 1 to 10 .mu.m in height, and the coating layer 18 is brought into contact with the flat and smooth surface 22A of the light-transmissive material 22 through the spherical beads 20 which are put between them. The spherical beads are 1 .mu.m or less in half bandwidth of the distribution of particle diameters and are made uniform in height projecting from the coating layer 18.

Abstract: This invention provides a reflecting screen with a wide angle of field and high luminance usable in a video projector or the like, and comprising a first sheet having a first surface having a diffusion layer for diffusing a projected image, and a second surface formed on a side opposite to the first surface and having a group of striped prisms of an optically transparent resin arranged so as to extend vertically, the prisms having a section in the shape of an isosceles triangle with a constant apical angle and sides of constant length; and a second sheet opposed to the group of prisms of the second surface of the first sheet, a surface of the second sheet opposed to the group of prisms being of a black color capable of absorbing transmitted light substantially; the first sheet and the second sheet being disposed parallel to each other.