| 摘要 |
<p>The invention relates to an apparatus and a method for measuring visibility and present weather. The apparatus comprises a light source (1) suited for directing a light ray toward the object (9) to be measured, a detector (3) suited for measurement of scattered light, said detector being adapted to measure light which is forward scattered from said object (9) to be measured, and computing means (12 - 15) adapted to differentiate the signal representing the forward scattered light from the signal representing stray light. According to the invention, the apparatus with the light source (1) comprises a pulsed light source, receiving means (19) for receiving directly backward reflected/scattered light pulses, and computing means (11) for computing the propagation delays of the different backward reflected components in the received pulse-shaped optical signal. <IMAGE></p> |
