Siemens engineers have produced extremely thin, miniature colour displays that can be printed onto paper or foil, enabling production at very low cost compared to conventional LCD panels.

The flexible miniature displays operate using electrochromic materials that change their colour when an electrical voltage shifts charges in their molecules.

Prototype Siemens electrochromic display. Photo: Siemens.

The aim is to use a printing process to manufacture the entire display, including control electronics, from conductive and semi-conducting plastics. This could make it feasible to use colour displays for new applications, even packaging.

The displays can be powered by printable batteries, although these currently only last a few months. Engineers are now working on optimizing the materials to react quickly enough to allow moving images to be displayed.

On show at the Plastics Electronics trade fair in Frankfurt, the first displays will become available on the market in 2007.