| 摘要 |
PROBLEM TO BE SOLVED: To realize an LED lighting device showing a high input without changing LED output.SOLUTION: This invention includes an LED 1 and a semisphere mirror 3. The LED 1 is configured in such a way that its light emitting part has a flat surface and point symmetric shape, a light emitting angle distribution is a Lambert distribution, the light emitting surface is a diffusion surface, the semisphere mirror 3 has an inner surface forming a reflection surface 3a, its center has a circular opening part, the reflection surface 3a is arranged to face against the LED, a normal line of the LED1 and an optical axis of the semisphere mirror 3 are coincided to each other, a spacing between the LED 1 and the semisphere mirror 3 is less than a curvature radius and dLED*D/2r≒dimage*NAimage is satisfied, where dLED is a size of the LED 1, r is a curvature radius of the semisphere mirror 3, D is a diameter of the circular opening part of the semisphere mirror 3, dimage is a size of an optical image and NAimage is a light focus light NA.SELECTED DRAWING: Figure 1a |
