A technique for a display device using a display panel with Lambert light distribution, such as a plasma display panel, which displays a bright image with less contrast deterioration. This device has a front sheet which is integrally or separately located in front of the display panel. The front sheet includes light guides which extend in the horizontal direction and have a virtually convex cross section in the vertical direction with their apexes on the light exit side. A light reflection layer and a light-absorbing layer are sequentially stacked on the lateral sides of the light guides.