INVERSE PRISM SHEET FOR BACKLIGHT UNIT AND THE BACKLIGHT UNIT USING THE INVERSE PRISM SHEET

摘要

An inverse prism sheet for a backlight unit and a backlight unit having the same are provided to determine shape and angle of an inverse prism according to light projection angles of dot patterns of a light guide panel, thereby realizing high luminance. A backlight unit includes an inverse prism sheet(440) for a backlight unit formed with prism patterns in the shape of stripe in a lengthwise direction at a bottom surface, wherein the prism patterns have a prism angle to project incident light of a light guide panel(420) perpendicularly with respect to a front surface of the inverse prism sheet. The prism patterns are different in inclination at right and left corners, in such a manner that an inclination angle of a corner(710) of a light incident part(A) is larger than that(720) of an opposite part(B) thereof. An apex angle of the prism patterns is in the range from 30° to 50° and preferably 38.9°.