| 摘要 |
<p>The lampshade is of cylindrical or turncated-cone shape with an open bottom. A screen is mounted slightly below the level of the top opening, and can have a reflective lower surface. There can be an annular gap between the screen and the side of the lampshade, and the screen can be removable. It can be in several sections one above the other, leaving room for heat to escape while preventing the light rays from doing so, and directing the latter downwards onto the working surface.</p> |
