| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the unnecessary lighting when vehicle temporarily passes through a dark place in travelling in the daytime by changing the illuminance to be a value darker than a predetermined illuminance when the inclination of the change of illuminance until the ambient environmental illuminance becomes lower than the predetermined illuminance is above a specific velue. SOLUTION: The side lamps L2 and the front lamps V1 are lighted when the ambient environmental illuminance Vf is gently lowered, and is lower than a first predetermined illuminance V1 at a time t1 or a second predetermined illuminance V2 at a time t2. When a vehicle temporarily passes through the dark in the day time travelling, the inclination of the lowering of the illuminance of the ambient environmental illuminance is quick. On this occasion, when the inclination of the change of the ambient environmental illuminance Vf is larger than a specific value, the predetermined illuminance V1, V2 are respectively lowered byΔV1,ΔV2. On the other hand, when the delay time Td exists from the detection to the lighting, a detaly time Td' obtained by further adding a timeαis also available. Whereby the undesired lighting can be prevented when the vehicle temporarily passes through a dark place.</p> |
