US 7,541,945 B2
Navigation system and landmark highlighting method
Yasuo Nakashima, Hekinan (Japan)
Assigned to DENSO CORPORATION, Kariya (Japan)
Filed on Nov. 14, 2006, as Appl. No. 11/598,645.
Claims priority of application No. 2005-331311 (JP), filed on Nov. 16, 2005.
Prior Publication US 2007/0115142 A1, May 24, 2007
Int. Cl. G08G 1/123 (2006.01)
U.S. Cl. 340—995.24  [340/995.23; 340/995.12; 340/990; 701/202; 701/211] 4 Claims
OG exemplary drawing
 
1. A navigation system displaying in a display unit a map and a landmark assigned to a spot, the system comprising:
a visits count storing unit that stores (i) identification information of a landmark assigned to a spot and (ii) a visits count relative to the spot;
a visits count update unit that updates the visits count in the visits count storing unit when the spot is visited;
a daily activity area defining unit that defines a daily activity area; and
a highlighting unit that
(i) refers to the visits count storing unit when the spot is included in a map display range in the display unit,
(ii) highlights the landmark when the visits count stored in the visits count storing unit is greater than a first predetermined value when the spot is included in the daily activity area, and
(iii) highlights the landmark when the visits count stored in the visits count storing unit is greater than a second predetermined value, which is smaller than the first predetermined value, when the spot is included in a not-daily activity area,
wherein
the daily activity area defining unit
(i) memorizes a first minimum value and a first maximum value in latitude and a second minimum value and a second maximum value in longitude within an activity range undergone for a predetermined time period, and
(ii) defines as a daily activity area a rectangular coordinate range defined by the first and second maximum values and the first and second minimum values.