NAVIGATION DEVICE ON VEHICLE

摘要

PROBLEM TO BE SOLVED: To provide a navigation device capable of judging which of multilayered road a vehicle is running without requiring high quality acceleration sensors and expressway information. SOLUTION: A light intensity detection means 13 for detecting light intensity and a position judging means 16 for judging which of multilayered road a vehicle is running by utilizing the light intensity that the light intensity detection means detects are provided. By paying attention to the variation quantity and variation pattern of light intensity detected by the light intensity detection means or the difference from the average of intensity, which of upper or lower sides of the multilayered road the vehicle is running can be discriminated, thus proper discrimination becomes possible with a simple constitution.