| 摘要 |
<P>PROBLEM TO BE SOLVED: To downsize a downlight by effectively utilizing the light of a lamp which is controlled in light by the suitable combination of a reflector and a cone. <P>SOLUTION: A light source 12, a reflector 14, and a nearly cylindrical cone coaxially arranged with the reflector are provided. The cone is formed as a cone reflector 20 of which the inner peripheral face is used as a reflective face and the inner peripheral face of the reflector is formed by a rotation ellipsoidal face. The light-emitting point 12a of the light source is arranged at a first focus F1 of the reflector, a second focus F2 is arranged at a position overlapped with an intersecting point Z of the standard line L2 which passes through the center line C of the cone reflector, has an inclination angle θ, and is connected to the opening edge 21 of the cone reflector and the inner peripheral edge 14e of the opening of the reflector, or arranged above the intersecting point Z. The inner peripheral face of the cone reflector has a rotating face shape to generate reflecting light having an inclination angle larger than a prescribed angle θ by reflecting the incident light from the light-emitting point 12a of the light source and obtaining the rotating face shape by rotating a part of a parabola. <P>COPYRIGHT: (C)2011,JPO&INPIT |
