A light collimating film has a sheeting having a first side and a second side, wherein the first side includes a series of prisms, and the second side includes a plurality of subwavelength optical microstructures. Another embodiment includes a back lighting display device having a lighting means, a display panel, and a sheeting having a first side and a second side, wherein the first side includes a series of prisms, and the second side includes a plurality of subwavelength optical microstructures. A preferred embodiment includes a back lighting display device having a first collimating film having a first surface with a subwavelength optical microstructure thereon and a second surface with linear prisms having an included angle of greater than about 95 degrees, and a second collimating film having a first surface with a subwavelength optical microstructure thereon and a second surface with linear prisms having an included angle of less than about 85 degrees.