| 摘要 |
A light source unit (10,10a,30) capable of considerably reducing the size of a vehicular lamp. An LED (12) is mounted on an optical axis (Ax) extending in the longitudinal direction of the vehicle with its light output directed upward, and a reflector (14,34) is provided above the LED (12) having a first reflecting surface (14a,34a) for collecting the light emitted by the LED (12) and reflecting the light generally in the direction of the optical axis (Ax). The first reflecting surface (14a,34a) is formed in such a manner that a distance (L) in a vertical direction from the LED (12) to the first reflecting surface (14a,34a) is approximately 10 mm in a preferred embodiment. Consequently, the size of the reflector (14,34) can be considerably reduced as compared with reflectors employed in conventional vehicular lamps. Moreover, the LED (12) used as a light source emits little heat, the reflector (14,34) can be designed without having to take into account the influence of heat generated by the light source. Furthermore, the LED (12) can be treated substantially as a point light source so that proper reflection control can be carried out even if the size of the reflector (14,34) is reduced. By mounting the LED (12) so that its light output is directed substantially orthogonal to the optical axis (Ax), moreover, it is possible to effectively utilize most of the light emitted by the LED (12) and reflected by the first reflecting surface (14a,34a). |
