Patent ID: 6335695
Filing Date: 2002-01-01
Classification: G01C,G09B

Abstract:
A map display apparatus comprising:a data storage portion for storing map data, the map data being generated by assuming that an area surrounded by particular longitudes and particular latitudes is one of a rectangle and a square; a display control portion for generating a map of a target area by using the map data stored in the data storage portion and a distortion correction coefficient, the distortion correction coefficient being for correcting a distortion of the map caused by difference in a ratio of a corresponding length in the map and an actual length with respect to a latitude; a distortion correction coefficient storage portion for storing distortion correction coefficients by a unit of a predetermined latitude width, wherein the display control portion reads a particular distortion correction coefficient corresponding to a latitude of a particular point in the target area from the distortion correction coefficient storage portion, and converts the map data using the particular distortion correction coefficient.