| 摘要 |
PROBLEM TO BE SOLVED: To improve a mechanical strength of a movement prevention mechanism which prevents a light guiding board from moving to the side of an arc tube of a light source lamp. SOLUTION: A light outgoing face 15a of a light guiding board 15 has an end 15e continuous to a side face 24, whose surface is a stepped surface 15f one step lower than a main surface including an effective light outgoing area 15c. A step forming part 51 orthogonal to the steeped surface 15f is formed at the boundary between the stepped surface 15f and the main surface. In such a condition that a reflector 34 is fitted to the side surface 24 of the light guiding board 15, a tip face 52 of a side board part 36 of the reflector 34 and the step forming art 51 of the light guiding board 15 abut on each other. It is thus possible to improve the mechanical strength of a movement prevention mechanism 50. |
