Original X-ray
Mrs Wilhelm Roentgen’s hand is quite unremarkable, except for the one thing that makes it a part of history. The bones in the first ever x-ray image taken by her husband in 1895 belong to her hand. Over a century later  x-rays are still in black and white, but Professor Bob Cernik at the University of Manchester may be about to change all that. This new technique will have many possible applications, from airport security and medicine, to visualizing ‘flaws’ in engineering projects.  

As Professor Cernik explains, colours are just different wavelengths of light. ‘The fundamental technique of getting fingerprints from materials using multi-wavelength x rays is not new, but getting an image from them relies on the fact that you’ve got a detector that is energy sensitive.’

3D image
Using highly advanced instruments and detectors developed at the Rutherford Appleton Laboratory in Oxfordshire, and the Daresmore Laboratory in Cheshire, his team devised a method of capturing all the wavelengths in an x-ray in order to create a 3D image.

‘What you can do is to take a sample,’ says Cernik, ‘it could be part of a suitcase or, for example, a biopsy sample. You then scan this in 3 dimensions through a very fine pencil beam of x rays. Using your single detector to look at the scattering from each point, you can build up a three dimensional image and tell what the sample is at each point of that image. That is effectively a Tomographic Energy Dispersal Diffraction Image, or TEDDI for short.’

New system
The process is incredibly time consuming, taking up to 19 hours for an image of a concrete core sample of four to five centimetres. A practical instrument depends on the sensitivity and on the detector’s ability to absorb incredibly high energy x rays. Cernik is leading a group who are producing a working system. ‘In the short term we would like to have our working prototype working within two years,’ says Cernik, ‘and the rest depends on investment. It’s possible that the first scanners could be working within a five year period.’