Patent ID: 7911701

Claim:
A micro lens array sheet for use in a backlight device, comprising: a sheet type substrate; and a plurality of micro lenses arranged on said substrate, said plurality of micro lenses each having a surface, the surface of said micro lens comprising a convex part having a spherical or elliptical surface and a peripheral edge part formed between said convex part and said substrate and curved in a concave shape, wherein said micro lens has a height from 17.5 μm to 22.5 μm and a lens diameter from 36.5 μm to 46.5 μm, said peripheral edge part has a width from 1 μm to 5 μm and a height from 1 μm to 5 μm, and when the surface of said substrate provided with said plurality of micro lenses is viewed from immediately above, the ratio of the area occupied by said plurality of micro lens to the total area of the surface of said substrate is at least 70%.