Head-up display

The present invention relates to a head-up computer display and in particular to a head-up computer display having an increased contrast range and/or an increased range of colours that may be displayed. An improved head-up display enables a user to view a light emitting display and an ambient environment simultaneously. The improved display comprises a light-transmissive block allowing the transmission of light from the ambient environment to the user's eye through the block from a first surface to a second surface opposing the first surface. A light emitting display is located on a third surface of the block, the third surface being substantially perpendicular to the first and second surfaces. A beam splitter has a plane surface arranged at substantially 45 degrees to the first and second surfaces, so as to reflect light from the light emitting display through the second surface. A shutter is located on the first surface and is adapted to block the transmission of light from the ambient environment to the user's eye. This provides a dark background for the light emitting display.