| 摘要 |
PCT No. PCT/SE87/00322 Sec. 371 Date Jan. 9, 1989 Sec. 102(e) Date Jan. 9, 1989 PCT Filed Jul. 6, 1987 PCT Pub. No. WO88/00157 PCT Pub. Date Jan. 14, 1988.An airfield marker light, comprising a casing to be flush-mounted in the ground and having a lower light source (4), an upper, a transparent cover plate (8) lying substantially in the ground plane M, and a refractive member (7) which divides the light bundle from the light source, so that two light beams (L12, L34) are emitted from the upper surface of the cover plate (8) in opposite directions at a small angle to the ground plane. The light source (4) emits a collected, substantially vertical light bundle, and the refractive member includes a light dividing prism (7) situated between the light source and the cover plate and having refractive planar surfaces (7a, 7b, 7c, 7d) obliquely oriented in opposite directions, so that the vertical light bundle is divided into two light bundle portions, directed obliquely upwardly in oppoiste directions, the light bundle portions upon passage through the cover plate being refracted in opposite directions in the upper surface (8a, 8b) of the cover plate. |
