| 摘要 |
This object aims to provide an optical sheet (1) with a set (S) so formed as to be repeatedly arranged on the upper surface of the sheet, the set (S) consisting of a plurality of ridges (1a - 1c) each having a shape of isosceles triangle with different base angles, whereby uneven brightness in accordance with distances from CCFL (2) can be eliminated and the optical sheet does not depend on an arranged position of the CCFL (2); and a backlight unit using the optical sheet. An optical sheet (1) used for a direct type backlight unit is provided with a number of convex ridges so formed as to be arranged on the upper surface of the optical sheet (1), wherein the ridges in a region of the optical sheet (1) corresponding to each CCFL (2) are comprised of further repeatedly arranged sets (S) of three kinds of ridges (1a-1c) with mutually different shapes. |
