The present paper describes a radiography technique to inspect low thickness samples, on the order of micra. The penetrating radiation are charged particles generated by a lithium fluoride screen irradiated by thermal neutrons. The film used to register the images is a solid state nuclear track detector and the experimental conditions to obtain the best radiography are provided. A digital system for data acquisition and image processing was also used.

A digital system to characterize solid state nuclear track detectors(SSNTD) has been developed. It was used in the study of two detectors and its performance evaluated by comparing the obtained results with those determined by using an analog system, already in use for such purpose. The comparison of the results together with the feasibility and rapidness in data acquisition have demonstrated the viability of the digital system to characterize SSNTD.

A LIXI(Light Intensifier X-ray Image) device has been employed in a real-time neutron radiography system. The LIXI is coupled to a video camera and the real-time images can be observed in a TV monitor, and processed in a computer. In order to get the real-time system operational, the neutron radiography facility installed at the IEA-R1m nuclear research reactor of the IPEN-CNEN/SP has been optimized. The most important improvements were the neutron/gamma ratio, the effective energy of the neutron beam, decrease of the scattered radiation at the irradiation position, and the additional shielding of the video camera. Several one-frame as well as computer processed images are presented. The overall Modulation Transfer Function for the real-time system was obtained from the resolution parameter p = 0:44 ± 0:04mm; the system sensitivity, evaluated for a Perspex step wedge, was determined and the average value is 0:70 ± 0:09mm.