Since neutrons penetrate matter very well, they are very useful to look at the interior of technical components and work pieces by transmission measurement - without destroying the samples. Some light elements as for example hydrogen or boron can be easily traced by neutron radiography, while they are practically invisible in a common X-ray picture. Neutron radiography has become a standard method for various applications, e.g. the inspection of adhesive joints in aircraft construction.

Neutron transmission radiography (NR) is based on the attenuation of the radiation during the passage through matter according to an exponential law. Since different materials have different attenuation performance, the neutron beam can be interpreted as an information carrier about composition and structure. The basic components of a neutron radiography apparatus is shown in the following figure: