1. A display system for displaying an image, the system comprising: a projector comprising at least one collimated light source; and a controller configured to: receive image data representing an image divided into columns; control the at least one collimated light source; and sequentially project, using the projector, an array of the columns of image data onto a reflector such that one column of image data is projected onto the reflector at any one time and the columns of image data appear superimposed on one another when reflected into an eye of an observer when the eye is stationary relative to the reflector; wherein the projected columns of image data produce an image visible to the observer when the observer's eye scans across the reflector in a direction perpendicular to the direction of orientation of the projected columns.