| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a surface light source device capable of reducing light leakage in the vicinity of the light source, to emit light uniformly, and capable of emitting the light of a narrow directive characteristic, to enhance light emission brightness. <P>SOLUTION: A light guide substrate 38 comprises a light introducing part 42 for introducing a light from a point light source 32, and a light guide panel body 41 for emitting the light from a light emitting face 44 to an outside. A large number of diffusion patterns 46 is provided in the light emitting face 44 of the light guide panel body 41. A low-refractive index layer 39 of refractive index lower than that of the light guide substrate 38 is formed on an under face of the light guide panel body 41, and a reflective layer 40 is formed on an under face of the low-refractive index layer 39. The point light source 32 is positioned in a position opposed to an end face of the light introducing part 42. A directivity conversion part 45 is provided on an upper face of the light introducing part 42. The directivity conversion part 45 is constituted by arraying radially V-grooved directivity conversion patterns 48. <P>COPYRIGHT: (C)2011,JPO&INPIT |
