As if speed cameras and cameras to trap motorists at traffic lights, in bus lanes and at box junctions weren’t enough, the Department for Transport (DfT) is considering a new camera to prosecute drivers wrongly using car-sharing lanes. The cameras will enable Alistair Darling, the transport secretary, to fulfil his ambition of introducing car-sharing lanes on motorways across the country.

At present there are only two car-share lanes in Britain — in Leeds and south Gloucestershire. Transport officials want to introduce more to cut congestion, but they require expensive policing to make sure there is more than one person per car.

The new infrared Cyclops cameras, designed by Laser Optical Engineering of Loughborough, would overcome this problem by detecting whether vehicles are carrying passengers. The cameras use an infrared wavelength that recognises the skin tones of driver and passengers so it can distinguish between humans and animals.

Known officially as vehicle occupancy monitors, the cameras are undergoing final testing, and the company says it is in talks with the DfT, as well as several local authorities. A prototype camera has already been tested on the A647 in Leeds, Britain’s first car-sharing lane, which was set up in 1998.

The Highways Agency plans to begin trials of a car-sharing lane on the M1 between junctions 7 and 10 when work is completed in 2008.

A DfT spokesman confirmed the department was considering infrared cameras as a means of monitoring car-sharing lanes. Darling has said that the idea works in America, so there is no reason why it cannot work in Britain.

“Car-pool lanes have an important role to play in making best use of road space as well as helping the environment and reducing congestion,” he said. “The Highways Agency will undertake further detailed investigation and design work before any final decisions are made.”