Device detects 'invisible' gas

The gas is seen as a black cloud in an image produced by the device

Scientists in Scotland have invented a laser machine which can trace killer gas leaks.

Experts at the University of St Andrews are finishing work on their prototype detector, which allows scientists to track down a wide range of gases invisible to the naked eye.

Dr Cameron Rae and Dr David Stothard, of the university's Photonics Innovation Centre, have already used their new gadget in the laboratory to find a cloud of methane escaping from a leaking hose.

It is able to produce live video pictures of an invisible gas.

Members of the St Andrews team have combined their latest laser technology with a cheap imaging idea borrowed from office photocopiers.

Dr Stothard said: "Having developed some really clever laser technology it looked like the project might stall because of the extremely high cost of infrared video cameras.

"Then I had the idea of using a mechanical scanning technique and optics similar to those used in a photocopier. It worked really well and the project is back on course."

He believes the invention has commercial potential, especially when applied to the home, where a dangerous gas leak could be found in seconds.

Wider uses

The breakthrough is already attracting interest among European energy companies, who believe it could safeguard lives and save money.

The use of the detector at petrochemical plants, where it can take days to locate a problem, could seriously reduce the risk to workers and the environment by rapidly tracking down and plugging any dangerous leaks.

The technology, though, could have wider uses.

Dr Rae remarked: "It is envisaged that the laser technology developed here will have more widespread use in, for example, medical diagnostic and therapeutic applications as well as telecommunications and defence."

Dr Rae and Dr Stothard are now working to make sure their finished prototype can be made lightweight and portable.

The team plans to set up links with industrial organisations, which will lead to a device suitable for field trials.

The project has been backed by funding from Scottish Enterprise, and is one of the first to be completed under its Proof of Concept scheme.