| 摘要 |
<p>An illumination system having a light source disposed along a central axis of the system is provided with a conical reflector coaxially disposed about the light source for forming an annular virtual image of an arc of the light source. A toroidal lens is coaxially disposed about the central axis for forming a circular real image of the annular virtual image of the arc at the input port of a utilization device.</p> |
