A navigation system is provided with: a position measuring device for measuring a current position of a movable body to which the navigation system is equipped; a storing device for storing aerial photograph data; a displaying device; and a display controlling device coupled to the position measuring...http://www.google.co.uk/patents/US5396431?utm_source=gb-gplus-sharePatent US5396431 - Navigation system with position measuring device and aerial photographic storage capability
