| 摘要 |
PROBLEM TO BE SOLVED: To provide a navigation device which allows it to be known immediately, when and from where departure has to be taken, in order to reach a destination on a target time.SOLUTION: A plurality of iso-departure time lines are drawn on a map through an iso-departure time line drawing process executed by a controller of the navigation device. On a display screen 6a, screens drawn are shown, having a map display 6b, a road choice display 6c, a route/destination display 6d, and a target time display 6e. For cases where arrival at a destination at 19:00 (target time) is desired, a search route from the present position is shown; while an iso-departure time line for 18:00, an iso-departure time line for 17:00, an iso-departure time line for 16:00, and an iso-departure time line for 15:00 are drawn. For cases where a user desires to arrive at the destination at 19:00, it is appropriate to start from halfway points at departure times displayed, together with the intermediate points on the respective iso-departure time lines. |
