Abstract: A car navigation system 1 includes a HDD map 110 and a cached map 109. Map data for entire area is stored in the HDD, and map data used by a route search unit 115 and a guidance unit 116 are stored in the cached map 109. A cached map area specifying unit 108 specifies map data files that should be stored in the cached map 109 for each navigation application, and stores the names of the specified map data files, linked to the respective navigation applications, into a navigation application consistency management table 103. A consistency judgment unit 104 monitors an update status of a data file of which name stored in the navigation application consistency management table 103, and stores the update status (completed or not completed) into the navigation application consistency management table 103.

Abstract: A navigation device includes: a storage unit that stores map data divided into a plurality of files for a predetermined map range; an acquisition unit that acquires map updating data for updating the map data; an extraction unit that extracts at least one file from among the map data files; and an updating unit that updates the map data by storing new map data files based upon the map updating data in the storage unit, after having deleted the map data files from the storage unit with the exception of the file extracted by the extraction unit.

Abstract: A car navigation system 1 includes a HDD map 110 and a cached map 109. Map data for entire area is stored in the HDD, and map data used by a route search unit 115 and a guidance unit 116 are stored in the cached map 109. A cached map area specifying unit 108 specifies map data files that should be stored in the cached map 109 for each navigation application, and stores the names of the specified map data files, linked to the respective navigation applications, into a navigation application consistency management table 103. A consistency judgment unit 104 monitors an update status of a data file of which name stored in the navigation application consistency management table 103, and stores the update status (completed or not completed) into the navigation application consistency management table 103.

Abstract: A map information update system has: a map display control apparatus; and a map information update apparatus. The map display control apparatus includes a map display control unit, a communication control unit, a map information transmission unit and a map information reception unit. The map display control unit controls the display device so as to update the map displayed on the display device based upon the updated information related to the map. The map information update apparatus includes a communication control unit, a map information update reception unit, a map display update data base unit, and an updated map information transmission unit that transmits information related to the map updated by the map information update unit to the map display control apparatus via the communication control unit.

Abstract: A map display apparatus includes a map data memory which stores map data necessary for plotting a map of a predetermined region; a map display which reads map data out of the map data memory and plots a bird's-eye view display by projecting the map data read out from the map data memory onto a projection plane which makes a projection angle with a plane of the map data read out from the map data memory, the projection angle being greater than 0° and less than 90°, the bird's-eye view display including identifying marks which identify items in the bird's-eye view display; and an identifying mark overlap preventer which prevents identifying marks from overlapping one another in the bird's-eye view display.

Abstract: A map information update system has: a map display control apparatus; and a map information update apparatus.

Abstract: A map display apparatus includes a map data memory which stores map data necessary for plotting a map of a predetermined region; a map display which reads map data out of the map data memory and plots a bird's-eye view display by projecting the map data read out from the map data memory onto a projection plane which makes a projection angle with a plane of the map data read out from the map data memory, the projection angle being greater than 0° and less than 90°, the bird's-eye view display including identifying marks which identify items in the bird's-eye view display; and an identifying mark overlap preventer which prevents identifying marks from overlapping one another in the bird's-eye view display.

Abstract: A map display apparatus includes a map data memory which stores map data necessary for plotting a map of a predetermined region; a map display which reads map data out of the map data memory and plots a bird's-eye view display by projecting the map data read out from the map data memory onto a projection plane which makes a projection angle with a plane of the map data read out from the map data memory, the projection angle being greater than 0° and less than 90°, the bird's-eye view display including identifying marks which identify items in the bird's-eye view display; and an identifying mark overlap preventer which prevents identifying marks from overlapping one another in the bird's-eye view display.

Abstract: A map display apparatus includes a map data memory which stores map data necessary for plotting a map of a predetermined region; a map display which reads map data out of the map data memory and plots a bird's-eye view display by projecting the map data read out from the map data memory onto a projection plane which makes a projection angle with a plane of the map data read out from the map data memory, the projection angle being greater than 0° and less than 90°, the bird's-eye view display including identifying marks which identify items in the bird's-eye view display; and an identifying mark overlap preventer which prevents identifying marks from overlapping one another in the bird's-eye view display.

Abstract: A navigation apparatus for displaying most appropriately information such as character strings, routes, etc., when a map is displayed by bird's-eye view display. The navigation apparatus includes a portion for calculating the present position on the basis of information from sensors, a portion for executing perspective conversion operation for displaying a map by bird's-eye view display, a portion for disposing the present position or the present position and a position representing a destination at the most suitable positions, a portion for controlling so that overlap of character strings can be eliminated, a portion for controlling the same character strings, a portion for displaying most appropriately a background such as lines and planes, a portion for controlling marks to be displayed, and a portion for executing graphic plotting by using the resulting map data.

Abstract: A map display apparatus according to the present invention, has a data conversion circuit that converts a plane map data to a bird's-eye view map data in a specific bird's-eye viewing direction in order to display a map in a bird's-eye view format; and an operating member that is operated to change the specific bird's-eye viewing direction.

Abstract: A navigation apparatus for displaying most appropriately information such as character strings, routes, etc., when a map is displayed by bird's-eye view display. The navigation apparatus includes a portion for calculating the present position on the basis of information from sensors, a portion for executing perspective conversion operation for displaying a map by bird's-eye view display, a portion for disposing the present position or the present position and a position representing a destination at the most suitable positions, a portion for controlling so that overlap of character strings can be eliminated, a portion for controlling the same character strings, a portion for displaying most appropriately a background such as lines and planes, a portion for controlling marks to be displayed, and a portion for executing graphic plotting by using the resulting map data.