The idea of printing a light bulb may seem bizarre, but US engineers are now developing an ink-jet printing technology to do just that. The research at the University of California in Berkeley will allow fully assembled electric and electronic gadgets to be printed in one go.

The idea was revealed at a December workshop on robotic algorithms in Nice. Instead of creating a casing and then laboriously filling it with electronic circuit boards, components and switches, the plan is to print a complete and fully assembled device.

The trick is to print layer upon layer of conducting and semiconducting polymers in such a way that the circuitry the device requires is built up as part of the bodywork.

When the technique is perfected, devices such as light bulbs, radios, remote controls, mobile phones and toys will be spat out as individual fully functional systems without expensive and labour-intensive production on an assembly line.