VISUAL DISPLAY WITH TIME MULTIPLEXING

A display device has a display, operable to generate a real image, and an optical system. In the optical system are at least two free-form reflective surfaces, S I and S2. At least one of the reflective surfaces is convex in one direction at substantially all points of its optically active area. Light rays from the display are reflected on SI before they are reflected on S2. The reflective surfaces SI and S2 are arranged to generate a virtual image from the real image on the display, by projecting light from the display to an eye position. The field of view occupied by the virtual image as seen from the eye position is greater than 50 degrees in at least one direction, preferably the direction linking the two eyes of an intended user.