| 摘要 |
An optical protection device for edges (1) of roads in a tunnel has a lamp chain (3) arranged along the edge (1) of the road and composed of signalling luminous elements (4) which are provided in each case with at least one light-emitting diode (5). A solar installation (10) is provided for the power supply. The luminous elements (4) of the lamp chain (3) are interconnected by an electric lead (6), and driven by control electronics (7) having a clock generator. The clock generator delivers a pulse train which in continuous-wave operation has a high frequency which can no longer be separately detected by the eye. A modulator controls the width of the pulses of the pulse train delivered by the clock generator as a function of the brightness outside the tunnel or the gallery. <IMAGE> |
