| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce ununiformity in brightness on an illumination surface. <P>SOLUTION: A lighting device 1 comprises a light source and reflection surfaces 2, 31. The light source has a light axis 111 nearly in parallel with a direction 91. The reflection surface 2 is sloped to the prescribed direction 91 and reflects light from the light source. The reflection surface 31 is provided at a light source side on the reflection surface 2, and reflects light included in a prescribed range from the light axis. In a triangle with a position P21, where the light axis crosses the reflection surface 31, a position P22 on the light axis, and a position P23, where a perpendicular line from the position crosses the reflection surface 31, as the vertices, an angle formed by a vertical angle at the position P21 is larger than an angle θ1 formed by the light axis and the reflection surface 2 similarly and is smaller than 90°. A segment r2 that has one end at the position P23 and the other end on the light axis and orthogonally crosses the light axis around the light axis when viewed from a direction 91 has one end at the position P13 and the other end on the light axis and forms an angle that is larger than 0° and is smaller than 90° for the segment r1 orthogonally crossing the light axis. <P>COPYRIGHT: (C)2007,JPO&INPIT |
