| 摘要 |
PURPOSE:To transmit light efficiently by putting the incidence end surface of an optical fiber closely to the secondary focus on a light source side where light is converged and forming a curved concave part like a spherical surface in the incidence end surface so that incident light from the secondary focus is below an angle of total reflection. CONSTITUTION:A reflection mirror which has a curved reflecting surface 5 for converging light from a light emission part 2 on the secondary focus 4 is provided at the periphery of a lamp 1. An optical fiber 8 formed by bundling many optical fiberous transmitters 6 with a converging body 7 whose end side is opened is provided, and a spherical or elliptic concave part 10 is formed in the converging end surface of the fiber 8; and transparent resin 11 is provided integrally outside the converging end surface 9, its incidence end surface 12 is provided nearby the secondary focus 4, and a spherical or elliptic concave part 13 is formed in the incidence end surface 12. The shape is so determined that the light from the secondary focus 4 is at <=30 deg. over the entire surface of the concave part 13. |
