Backlight unit and display apparatus having the same

摘要

A display apparatus includes a display panel, a plurality of spaced apart point light sources outputting light and each having an orientation angle greater than or equal to about 50° and less than about 90°, and an optical plate interposed between the display panel and the point light sources. The optical plate has a base comprising front and rear surfaces and a plurality of convex sections formed on the front surface of the base. Each convex section has a cross section perpendicular to the front surface in which the cross section has a form of a segment of an ellipse including an arc of an ellipse and a chord linking both ends of the arc while satisfying an equation,;1.0when a minor axis of the ellipse has a length of 2a, and a major axis of the ellipse has a length of 2b.

主权项

1. A display apparatus comprising:
a display panel; a plurality of spaced apart point light sources each having an orientation angle that is greater than or equal to about 50° and is less than about 90°, the orientation angle being a zenith angle of an output light ray representing a highest intensity among light rays output from each of the plurality of spaced apart point light sources; and an optical plate interposed between the display panel and the point light sources and comprising a base comprising front and rear surfaces and a plurality of convex sections formed on the front surface of the base, the optical plate being structured to encourage internal reflection therein of light beams received thereby at or substantially near the orientation angle so as to thereby laterally reposition the light of those beams before they are ultimately output from the optical plate, wherein the point light sources are provided along a first plane and a parallel second plane is defined as extending through the optical plate and comprising a plurality of cells each corresponding to one of the point light sources in a one-to-one correspondence, and wherein each cell comprises a plurality of regions sequentially disposed across the cell, and the convex sections within different ones of the regions have densities different from those of adjacent other regions of the cell.