| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable a luminaire unit for forming a cutoff line in a headlight for a vehicle to carry out a light distribution control with accuracy in a compact and simple structure. <P>SOLUTION: The luminaire unit 20 is structured of a projection lens 22 arranged on a light axis Ax extended in a back-and-forth direction of a vehicle, and a semiconductor light-emitting element 24 having a light-emitting chip 24a with a lower end edge 24a1 linearly formed and arranged in a forward direction with the lower end edge 24a1 positioned on the light axis Ax at the rear of the projection lens 22, and it is so made that a part CL1b of a horizontal cutoff line CL1 is made as a reversed projection image of the lower end edge 24a1. At that time, the projection lens 22 is so structured that light from a point on the light axis Ax at the lower end edge 24a1 is irradiated as parallel light within a vertical cross section, while light from a point on the light axis Ax at the lower end edge 24a1 is irradiated as diffused light. This enables to form a small light distribution pattern P1b extended along the horizontal cutoff line CL1 in a simple optical system. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
