| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lighting unit that improves front luminance while optical deflection elements of a light guide plate are made hardly visible. <P>SOLUTION: In the lighting unit 7 including a surface light source device 2 having a light source 11, the light guide plate 10 with an incident end surface, an emitting surface, and an optical deflection surface, and a reflection sheet 9, a diffusion sheet 3, and a diffusion and condensing sheet 4 for coping with both of diffusion of light and improvement of luminance, the optical deflection elements 13 provided on an optical deflection surface 12 are extended in a first direction in parallel with the end surface, and are arranged in one-dimensional array arranged in a second direction perpendicular to the end surface. The light guide plate 10 is divided into two zones such as the zone A wherein an arrangement pitch of the optical deflection elements is 500 μm or more and the zone B wherein the arrangement pitch of the optical deflection elements is less than 500 μm. The diffusion and condensing sheet 4 diffuses light emitted from the zone A in one-dimensional direction or two-dimensional direction at an angular distribution wider than the light emitted from the zone B. <P>COPYRIGHT: (C)2013,JPO&INPIT |
