Backlight unit including array of hyperbolically-shaped micro lenses

摘要

A backlight unit includes a light source and a two-dimensional micro lens array (MLA) sheet including a plurality of lens unit each having a conic lens shape with a cross-section, taken through the lens axis, having a shape defined by the equation:;y=x2/r1+1-(1+k)⁢(1/r)2⁢x2where k is a constant with a value of less than or equal to −1, and r is the radius of curvature at the peak of the lens unit.

主权项

1. A backlight unit comprising:
a light source; and a micro lens array (MLA) sheet comprising a plurality of lens units two-dimensionally arranged thereon, wherein the light source has the micro lens array (MLA) sheet, a prism sheet, and a reflective polarizing film, sequentially stacked thereon or, wherein the light source has a prism sheet, the micro lens array (MLA) sheet, and a reflective polarizing film, sequentially stacked thereon, wherein each lens unit has a conic lens shape of which a vertical cross-section taken in a lens center is represented by the following Expression 1:y=x2/r1+1-(1+k)⁢(1/r)2⁢x2[Expression⁢⁢1] where k is a conic constant, and r is a radius of curvature at a peak of the lens unit, wherein, k≦−1.