A backlight for a stereoscopic 3D liquid crystal display apparatus includes a light guide having a light emission surface and an opposing light extraction surface, a first side extends between the light emission surface and the light extraction surface, and a second side extends between the light emission surface and the light extraction surface, the second side opposing the first side. A centerline extends parallel to the first side and second side and is equidistant from the first side and the second side. A center elongated prism extends along the centerline and forms a portion of the light extraction surface. A plurality of elongated prisms extend parallel to the center elongated prism wherein the prisms are progressively more canted for each subsequent elongated prism further from the center elongated prism. A plurality of light sources disposed along the first side and the second side.