| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical sheet which exhibits superior light extraction efficiency, or a master mold thereof, and an optical device.SOLUTION: A manufacturing method for a concavo-convex patterned sheet involves; preparing a base sheet having a concavo-convex structure X with a smallest pitch Pof 2-200 μm formed on one surface thereof, placing a monoparticulate-film etching mask on the surface with the concavo-convex structure X, and forming a concavo-convex structure Y thereon, which has a refractive index gradient effect on incident light, by means of a dry etching method using the mask, thereby forming a concavo-convex structure Z comprising the concavo-concave structure X superimposed with the concavo-convex structure Y. A method of placing the monoparticulate-film etching mask includes; a dripping step for dripping a dispersion liquid comprising particles dispersed in a solvent having a specific gravity lower than that of water onto a surface of water in a water tank; a monoparticulate-film forming step for forming a monoparticulate-film comprising the particles on the water surface by evaporating the solvent; and a transfer step for transferring the monoparticulate-film onto the surface of the base sheet with the concavo-convex structure X. |
