Patent ID: 7023418

Claim:
A display device comprising: a display sheet; a light guide sheet, a surface of which is in direct contact with a surface of the display sheet; and a light source placed on at least one side of the light guide sheet, wherein the light guide sheet is provided with a specific number of grooves to have a specific shape and a specific depth on a surface opposite to the surface of the light guide sheet joined to the display sheet in parallel with the light source at a specific pitch, the pitch of the grooves is corresponding to a pixel of the display sheet, and the thickness of the light guide sheet is from not less than 0.1 mm to not more than 2 mm, the depth of the groove is from not less than one fifth to not more than one third of the light guide sheet's thickness, and a tip angle of the groove is from not less than 60 degrees to not more than 100 degrees.