Movable optical scanning for N-S movement in a map display navigational apparatus

摘要

A navigational apparatus, for use in a piloted craft in which a map is displayed pictorially on a screen, representative of the terrain over which the craft is passing. The apparatus employs a moving film strip, a light source and known means to focus and project the image onto a screen. The light source is adapted for translational movement across the width of the film synchronously with an optical scanning device placed between the film and the screen and also movable across the film, so that N-S scanning of an individual film frame may be effected. E-W scanning of the film frame is effected by advancing the film in the film transport.