Patent ID: 7581867

Claim:
A brightness enhancement article for providing light from a light guiding plate surface, the brightness enhancement article comprising a plurality of light collecting structures, wherein adjacent light collecting structures are arranged to vary their direction along their length on the light-providing light guiding plate surface, each light collecting structure comprising: (a) an input aperture optically coupled to the light-providing surface; (b) an output aperture distal from said input aperture, wherein the output aperture has a surface area that is larger than the surface area of the input aperture and wherein the width of the output aperture varies over the length of the light collecting structure alone the light guiding plate surface; and, (c) a pair of curved side walls extending along the length direction and extended from the output aperture toward the input aperture; wherein, in a cross section taken orthogonally with respect to the length direction, the curved side walls approximate a parabolic curvature.