Roundel

A roundel was a key feature of the Doctor's TARDIS. Roundels were mainly used as a decorative feature, although occasionally they did actually fulfill a function.

The First Doctor's TARDIS had basic white roundels on the wall, circular in shape. They were indented into the wallpaper. (TV: An Unearthly Child) The Third Doctor added plastic furnishings to the edges of the roundels. One of them then became the replacement for the scanner. Later, his TARDIS had reverted to its original design. (TV: The Three Doctors)

In the Eighth Doctor's TARDIS (the Victorian Parlour) the Roundels do not feature, however around the edge of the Time Rotor there are circular cut-outs in the support beams. The clock faces around the wall also carry on the many circles theme.

In the Ninth Doctor's first control room, the walls of the TARDIS featured backlit hexagons. (TV: Rose). Early on the dim light provided the gloomy look, however by the time of The Tenth Doctor, overhead lights added to the TARDIS's illumination, so the Roundels now fulfilled a mainly decorative function.

In the first of The The Eleventh Doctor's Control Rooms, with the Rather whimsical Steam-punk inspired design, not so many Roundels featured, however there was a larger circular screen on the wall.

In the latest control room, with its darker, more gloomy feel, the Roundels have returned, in the form of blue and red neon circles. They contribute a brighter feel to the overall darkness of the TARDIS, and also add to the machine like design.