| 摘要 |
PURPOSE:To obtain a uniform projection spot on a light guide without using any optical component such as a lens by arranging the optical axis of a halogen lamp at a specific angle to the optical axis of the light guide and setting its focus on the optical axis of the light guide. CONSTITUTION:The optical axis of the halogen lamp 2 is arranged at the specific angle to the optical axis of the light guide 1, so the brightest luminous flux component in the part of the ring of annular luminous flux is made incident almost aligned with the optical axis of the light guide 1. Further, a reflecting mirror 5 is arranged between the focus (b) of the halogen lamp 2 and the light guide 1 nearby the light guide. The reflecting mirror 5 reflects light crossing the optical axis L1 of the light guide 1 in the light emitted by the halogen lamp 2 behind the focus (b) and guides it to the light guide 1. Consequently, the uniform projection light spot is obtained at the other end of the light guide. |
