| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem that when a traveling vehicle unexpectedly enters a tunnel, even an available function for automatic flashing using an optical sensor possibly do not operates quick enough for imaging from the traveling vehicle. SOLUTION: Disclosed is a navigation device 1 comprising a GPS positioning means 11 of detecting a current position, an HDD recording and reproducing means 13 of storing position information on tunnels, an imaging unit 181 which picks up images, a light emission unit 182 which emits light, a flash-ON mode in which the light emission unit 182 is made to emit the light for imaging and a flash-OFF mode in which the light emission unit 182 is not made to emit light for imaging, the optical sensor 184 which detects the lightness of light, and a control means of selecting the flash-ON mode when the lightness of light detected by the optical sensor 184 is not larger than a threshold and the flash-OFF mode when the lightness is larger than the threshold, while a control circuit 12 as the control means selecting the flash-ON mode whenever the current position is in a tunnel without reference to the lightness of light detected by the optical sensor 184. COPYRIGHT: (C)2009,JPO&INPIT |
