| 摘要 |
At least one lamp (3a, 3b) is disposed in a casing (1) having a transparent, flat cover (2), from which a well-defined light beam is emitted. The cover has a planar external surface (9) and a stepped internal surface (8). The lamp (3) is adapted to emit light rays (L2) impinging substantially at right angles on the stepped surface portions of the cover, so that the light rays, upon refraction at the planar external surface, are emitted at a desired small angle. |
