| 摘要 |
PROBLEM TO BE SOLVED: To provide a miniaturizable planar luminaire capable of restraining generation of leaked light. SOLUTION: On the transparent board un-facing surface 31d of a light guide body 31, plural flat parts 34 parallel to its transparent board facing surface 31b are formed in a step-like shape by interlaying tilting surfaces 35 tilting toward a tip surface 31c so as to be sequentially lowered from its point-like light source facing surface 31a toward the tip surface 31c. When light entered from the surface 31a is transmitted to the tip surface 31c side part by repeating reflection on the surface 31b and the surface 31d, the reflection angles by the surface 31b and the flat parts 34 are kept equal to or more than a critical angle because the flat parts 34 are parallel to the surface 31b. Accordingly, since the light is transmitted to the tip surface 31 side part without leaking outside (closed), luminance of the system can be improved. |
