A display system for displaying a virtual image to a viewer superimposed over a real object. The virtual image is conformal, meaning that the virtual image conforms to the real object along the line of sight of the viewer during movement of the viewer relative to the object. If a viewer changes his line of sight, the virtual image changes to conform to the real object along the changed line of sight The display system comprises a camera adapted to be mounted to the head of a human viewer and display apparatus adapted to be placed in front of at least one eye of the human viewer, the display apparatus being physically connected to, and in a fixed spatial relationship with, the camera. A method of displaying conformal virtual images using this apparatus is also described.
