| 摘要 |
<p>Marker light e.g. for airfields with a casing adapted to be flush-mounted in the ground. A lower light source (2) emits an upwardly directed, collected bundle of light (L1, L2), which enters into a prism (4) with a lower planar surface and upper saw-tooth formations (17a, 17b), where the light rays are totally reflected and refracted obliquely upwards in two opposite directions. These rays will meet saw-tooth formations (16a, 16b) of an upper transparent cover plate (3) at an essentially right angle, said cover plate (3) having un upper, essentially planar or in two different directions slightly inclined surface (3a, 3b), where the light rays (L1', L2') are refracted so as to form two light beams (L1'', L2'') with a desired elevational angle relative to the ground level plane.</p> |
