Evaluation of scattered neutron component in thermal neutron radiography image: Influence of scattered neutrons and unparallelness of incident neutron beam

Analysis of thermal neutron radiographic images are performed using neutronic methods. Analytical expressions for the behaviour of scattered neutron component and image distortions due to the unparallelness of the incident neutron beam are shown. Numerical results are compared with the neutron radiographic images of simple rectangular polystyrene test sections of various thickness. Suggestions for the optimum distance between the test section and the converter have been given.