The present invention provides A direct-type backlight having: a resin
sealing member including at least one resin layer, which has a light
reflecting section formed on the outermost surface of the resin sealing
member; an optical semiconductor element sealed by the resin sealing
member; and plural circular light scattering grooves formed
concentrically on at least one surface of the resin layer, wherein an
area of a circle in the center and an area among the respective
concentric circles are substantially the same.