Cold neutron and monochromatic X-ray micro-tomography

Both neutrons and X-rays have very interesting properties for tomography. Tunable monochromatic X-ray beams were used for element sensitive tomography of samples containing heavy elements using the K-edge dichromatic scanning technique. This research was done at the high-energy beam-line of the ESRF (France). A new set-up has been build for cold neutron tomography at the spallation source SINQ at PSI (Switzerland). The high flux cold neutron beam transmissions are observed with a CCD camera via a neutron-to-visible-light converter. Many samples have been investigated with parallel beam geometry. At the moment the conversion-screen resolution is about 230 mum. A neutron focussing lens was installed to make a cone-beam geometry. With this set-up, the resolution will increase by the magnification. Software for computer reconstruction for parallel neutron and X-ray beams and neutron cone beams have been developed.