| 摘要 |
PROBLEM TO BE SOLVED: To provide a light source having a compact structure and occupying less space, for an illuminated advertising board, an illuminated signboard, an illuminated display, an illuminated staircase, an illuminated floor, etc. SOLUTION: Light-emitting diodes 12 serving as primary light sources are installed adjacent to the ends of a round light guide rod 13 made of an acrylic resin to serve as a secondary light source, on which light reflecting parts 14 made of conical recesses of equal sizes are arranged on the outer periphery of one side (back) at intervals which get narrower from each end toward the center. Light rays produced by the light emitting diodes 12, after entering the light guide rod 13 through each end, reach each light reflecting part 14 either directly or via reflections inside it, and are radiated outward, via light reflections occurring there, from the outer periphery of the other side (front) radially opposed to the light reflecting parts 14. Therefore, articles or parts to be illuminated which adjoin to the light radiating parts of the light guide rod 13 are illuminated either directly or indirectly via a light guide plate 15 installed adjacent to the light guide rod 13. |
