A liquid crystal display (LCD) of the type used to represent numerical figures. Although liquid crystal (LC) flows like a fluid its molecular arrangement is not completely disordered. An LCD has a film of LC sandwiched between crossed polarizers and set on top of a mirror. In the 'off' state light is able to traverse both polarizers to reach the mirror because it gets rotated through 90 degrees by the LC. In the 'on' state an electric field applied across the LC alters its molecular alignment & hence its polarizing properties; light cannot traverse both polarizers to reach the mirror and the display appears black.