| 摘要 |
PROBLEM TO BE SOLVED: To prevent diffusion patterns from being seen raising in the vicinity of a point light source in a surface light source device uniformly dispersing light emitted from one point light source through dispersion patterns so as to radiate in uniform luminance from a light radiating face. SOLUTION: In this surface light source device, one point light source 40 is arranged on one side end face of a light guide plate 32, and diffusion patterns 36 are formed on the bottom face of the light guide plate 32. The diffusion patterns 36 are arrayed fan-like centering the point light source 40, the pattern densities of the diffusion patterns 36 are set to be large near the point light source 40, and the diffusion pattern densities are set to be gradually smaller as approaching the point light source 40. Further perspective angles being seen respective diffusion patterns 36 from the point light source 40 are set to be large far from the point light source 40, and are set to be gradually smaller as approaching the point light source 40. |
