| 摘要 |
<p>The lighting fixture is of the type comprising a source of illumination 1 and a reflector of the elliptical type, that is to say composed of a reflecting cap 4 which has a transverse opening 9 and whose cross-section is semi-elliptical, at the focus of which the light source 1 is placed and of a virtual symmetrical part, beyond the opening 9, at the focal plane P of which the light from the source 1 is made to concentrate by the cap 4. It comprises an opaque frustoconical sleeve 20, hollow and empty, whose large diameter, called "entrance" diameter, D, is equal to the diameter of the opening 9 of the cap 4 and whose height h is substantially equal to the distance which separates the plane of the opening 9 from the focal plane P of the virtual part in order that, on the one hand, the small diameter, called "exit" diameter, d, is located substantially in the said focal plane P and that, on the other hand, the slope of this sleeve is close to the line parallel to the outermost reflected rays, the latter forming the periphery of the light spot present in the focal plane P. <IMAGE></p> |
