Improved contrast segment display unit

The viewed part of the segmented display uses essentially the same colour pigmentation as the surrounding light absorbing area. The colouring of the viewing or illuminated segment area is a coating of the inside of the segment at the anode whereas the light absorbing coating is on the outside surface of the anode unit. The light absorbing layer is also a non-luminescent white substance, e.g. aluminium oxide, and the result is the luminescent colour of the lighted segment is quite different to the background light absorbing section. A segment comprises an indirectly heated (7) cathode (8) with control grid (9) and the anode (2) with pigmented display area (5). The surrounding light absorbing area (6) is on the outer of the segment so that a wider display is achieved.