1. A display system for displaying an image, the system comprising: a projector comprising at least one collimated light source; and a controller for receiving image data and controlling the light source, configured such that, in use, an array of columns of image data representing an image are projected sequentially onto a reflector such that, due to persistence of vision they appear superimposed on one another when reflected into the eye of an observer and such that, when the observer's eye moves in a direction perpendicular to the direction of orientation of the projected columns the observer can view the image.