Patent ID: 6820001
Filing Date: 2004-11-16
Classification: G01C,Y10S

Abstract:
A navigation device for vehicle comprising:map data providing means for reading map data from a recording medium; pre-reading process means for receiving a destination, detecting a current position of a vehicle, determining a route from the current position of the vehicle to the destination according to the map data provided from the map data providing means, setting an area of a first map, which corresponds to a first part of the route associated with a first type of road, to a first range in a pre-reading process and setting an area of a second map, which corresponding to a second part of the route associated with a second type of road, to a second range in the pre-reading process such that map data size of the area of the second range is less than map data size of the area of the first range, such that the first type of road is indicated by a first road attribute and the second type of road is indicated by a second road attribute, wherein the first type of road differs from the second type of road according to the first road attribute and the second road attribute, and wherein the first type of road denotes a general road other than a throughway, and the second type of road denotes a throughway; data storing means for storing both first map data, which corresponds to the first map area set by the pre-reading process means and is provided from the map data providing means, and second map data, which corresponds to the second map area set by the pre-reading process means and is provided from the map data providing means, in the pre-reading process; and guiding means for guiding the vehicle to take the route to the destination according to both the first map and the second map which are indicated by both the first map data and the second map data stored in the data storing means.