Light speed

Bletchley Park-based Ceravision has partnered with motor-racing team West Surrey Racing to demonstrate the effectiveness of a novel energy-efficient lighting system on a BMW race car that it then tested at Silverstone, the home of British F1 Grand Prix.

Ceravision's so-called 'Ecolumination technology' is a lighting system that uses microwave technology to power electrode-less bulbs. The bulbs are simple to adapt to existing designs and are mercury-free.

Here's how they work: first, microwave energy at a frequency of 2.4GHz is focused into a small transparent glass ampoule (called a burner) containing a noble gas at low pressure and microgramme quantities of selected metal halide salts.

The microwave energy is focused into the waveguide containing the burner, which forms an electric field ionizing the noble gas molecules to rapidly form a gas plasma within the glass ampoule. The plasma then begins to vapourise the metal halide salts present, and the plasma and metal halide salts combine to emit light.