| 摘要 |
There is provided a light automatic ON/OFF control device 1 that prevents botheration and strange feelings caused by an ON/OFF operation of a head light 50 by an influence of black clouds or white clouds in a visual field range of an illuminance sensor. A forward illuminance sensor 12 for detecting illuminance forward of a vehicle and an upward illuminance sensor 14 for detecting illuminance upward of the vehicle, wherein when the output of both the illuminance sensors 12, 14 is smaller than an ON illuminance threshold, the head light switches on, and when equal to or more than an OFF illuminance threshold higher than the ON illuminance threshold, the head light switches off. Particularly since the visual field range of the upward illuminance sensor 14 is set to an angle of 45° or more, which is wider than that of the conventional visual field range, even if white clouds or black clouds appear above, an area ratio shown by these clouds within the visual field range of the upward illuminance sensor becomes small. Therefore the influence is reduced and the output of the upward illuminance sensor 14 does not cross the ON illuminance threshold or the OFF illuminance threshold. Accordingly an ON state or an OFF state of the head light does not change to prevent a temporal ON/OFF operation thereof. |
