Researchers develop ‘sharper X-ray’

Researchers at the Daresbury Laboratory in the UK are developing a technique known as diffraction enhanced imaging, which produces sharper images than conventional X-rays.

Advanced imaging technology developed to detect tumours in the human body can also be used to test other materials in the aerospace and automotive industries.

Researchers at the Daresbury Laboratory in Cheshire, which specialises in nuclear science, are developing a technique known as diffraction enhanced imaging, which produces sharper images than conventional X-rays.

The technique uses a crystal between the object being studied and the detector. The crystal diffracts rays that have been scattered by the object – which are discarded by conventional X-ray machines – into the detector. Two-dimensional images can then be created by scanning both the object and the detector through the beam.

The technology will allow specialists to spot damage to soft tissue, which is not picked up by conventional X-rays. It can also be used in industries such as aerospace for non-destructive testing of new materials, said Dr Robert Lewis, head of medical imaging at Daresbury.

For instance, carbon fibres, used to make aircraft such as the Airbus A380 lighter and more fuel efficient, can be tested for faults using the technique, he said.

‘The new technology is vastly superior to a conventional machine for looking at composite materials. Normal X-rays cannot see the difference between the carbon fibre and the matrix in which it is embedded.’

The technology can also be used by firms to detect faults, and for quality control during production, he said. ‘The technology shows up edges, so bubbles and cracks are incredibly clear.’

At present companies have to take samples of their materials to Daresbury to be X-rayed, but the organisation is planning to develop a portable version of the technology, and license it to a manufacturer to produce.

The project is part of the laboratory’s £150m Centre of Accelerator Science Imaging and Medicine (Casim) programme, which aims to create a specialist centre for researching nuclear physics and developing technologies for use in medicine and industry.

‘Given that there is a huge explosion of accelerator research at the moment, we felt the UK would be left behind if we did not invest in this area,’ said Lewis.

The technology can also be used by car manufacturers to follow the flow of oil through an engine.

A radioactive isotope is attached to an element, such as carbon, and sent through the engine. This radioactive ‘tag’ then produces two gamma rays that are picked up by detectors at both ends, allowing engineers to develop a 3D picture of what is happening within the engine.

‘It is very difficult in something the size of an engine to understand what the actual oil flow is, as it can get trapped in crevices. The technology allows you to visualise this in 3D and see how things move over time, while the engine is running,’ said Lewis.

The X-ray and tagging projects have received funding from the government, and the research team is now planning to develop the technologies further for use in the health service and in industry.