Map display method in navigation system and navigation apparatus

• US 6,825,855 B2
• Filed: 11/20/2001
• Issued: 11/30/2004
• Est. Priority Date: 04/13/2001
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation), Mitsubishi Jidosha Kogyo Kabushiki Kaisha, Mitsubishi Jidosha Kogyo Kabusiki Kasha
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation), Mitsubishi Jidosha Kogyo Kabushiki Kaisha
• Inventors: Asano, Shigeaki, Nakane, Shigeki, Watanabe, Atsushi, Maeda, Atsushi
• Primary Examiner(s): Brier, Jeffery
• Assistant Examiner(s): YANG, RYAN R
• Application Number:
  US09/988,750
• Publication Number:
  US 20020149586A1
• Time in Patent Office: 1,106 Days
• Field of Search: 345/629, 345/630, 345/634, 345/635, 345/636, 340/988, 701/208
• US Class Current: 345/629
• CPC Class Codes: G01C 21/3635 Guidance using 3D or perspective road maps
• CPC Class Codes: G06T 17/05 Geographic models

Abstract

A map display method in a navigation system has a bird'"'"'s-eye view display function of displaying a map image in conjunction with a background image. The map display method in a navigation system has a step of displaying a horizon that indicates a boundary between the map image and the background image, and is rounded at least in part. Besides the bird'"'"'s-eye view display effect, the method can enhance a sense of realism of the bird'"'"'s-eye view display. Thus, it can solve a problem of a conventional method in that the bird'"'"'s-eye view display effect cannot be achieved satisfactorily because the conventional method displays a pseudo horizon in a straight line to indicate the boundary between the map image region and the background image region.

Claims

1. A map display method in a navigation system having a bird'"'"'s-eye view display function comprising:

displaying a map image in conjunction with a background image;

displaying a horizon that indicates a boundary between the map image and the background image, the horizon being rounded at least in part;

preparing a plurality of background data with different degrees of roundness of the horizon;

selecting one of the background data in accordance with a vehicle speed; and

displaying the background data by superimposing the background data upon the map data.

2. The map display method in a navigation system according to claim 1, wherein the horizon is rounded within a display inhibition region which is adjacent to the background image, and in which display of a land mark or a destination mark of the map image is inhibited.

3. A navigation apparatus comprising:

a bird'"'"'s-eye view generating section for generating a bird'"'"'s-eye view from map data input in accordance with a display target area;

a display section for displaying the bird'"'"'s-eye view;

a horizontal background data generating section for generating background data including a rounded horizon as a background image to be superimposed upon a map image corresponding to the map data

a memory for storing a plurality of background data with different degrees of roundness of the horizon; and

a horizontal roundness decision section for deciding a degree of roundness of the horizon in response to a speed of a vehicle detected by a vehicle speed sensor,

wherein said horizontal background data generating section reads from said memory the background data with the degree of roundness determined by said horizontal roundness decision section.

4. The navigation apparatus according to claim 3, wherein the display target area is decided in accordance with a display scaling, a display angle, a display position and a bearing of a vehicle.