| 摘要 |
<p>PURPOSE:To obtain a warning information to prevent an accident due to freeze of a road surface by so arranging a projector, a light receiver and a road surface temperature as to discriminate conditions of a road surface based on the output of the receiver and the output of the road surface temperature while the projector is driven based on the road surface temperature. CONSTITUTION:A support 22 is erected on one side of a road 21 and a projector 24, a irregular reflection receiver 25, a regular reflection receiver 26 and a light projection level measuring device 27 are mounted on a support arm 23 while a road surface temperature 28 is provided on the support 22. The projector 24 is driven by a fixed power with a stabilizer 29 and controlled with a projector driving section 46. The receiver 25 is provided with light receiving elements for infrared light and visible light respectively, the receiver 26 with a light receiving element 33 for visible light and the measuring device 27 with a light receiving element 30 for visible light. Outputs are applied to a logic circuit 44 by way of an amplifier 36 comparators 41-43. The outputs of the circuit 44 and the temperature 28 are inputted into a computation circuit 45 to output a road surface conditions discriminating signal while the supply of the power source is controlled with a driving section 24 according to the temperature of the road surface.</p> |
