| 摘要 |
<P>PROBLEM TO BE SOLVED: To establish light-distribution characteristics of a lighting device using a light guide plate at a required wide light-distribution state. <P>SOLUTION: A floor surface in a range right under the lighting device 10 is mainly illuminated with emitting light L0 emitted from a location where a prism body 16 of an emitting surface 14b of the light guide plate 14 is not arranged, and a floor surface in an outer range rather than the range above is mainly illuminated with emitting light L1 refracted by the prism body 16. A prism 16a of the prism body 16 can attain required wide light-distribution by putting together a light-distribution distribution of the emitting light L1 refracted by the prism body 16 and a light-distribution distribution of the emitting light L0 emitted from the location where the prism body 16 of the emitting surface 14b of the light guide plate 14 is not arranged, since the light-distribution distribution of the emitting light L0 from the emitting surface 14b of the light guide plate 14 and the light-distribution distribution of the emitting light L1 attained by being refracted by the prism body 16 are formed in a shape having a complementary relation to obtain desired light-distribution characteristics. <P>COPYRIGHT: (C)2012,JPO&INPIT |
