Development of a pulsed neutron three-dimensional imaging system using a highly sensitive image-intensifier at J-PARC

To realize neutron energy resolved three-dimensional (3D) imaging in the resonance neutron energy region, a camera system coupled with a high sensitivity and high frame-rate gating image-intensifier was developed. The resonance absorption 3D imaging was successfully demonstrated at the pulsed neutron source of the Japan Proton Accelerator Research Complex (J-PARC). The camera system allowed us to obtain a time-of-flight (TOF) image of 2352 (W)×1726 (H) pixels resolved into a narrow energy range. 3D images with enhanced contrast at corresponding resonance energy regions for cylindrical Au, Ta, and In samples were reconstructed by convolution filtered back-projection (FBP) and maximum likelihood expectation maximization (MLEM) methods. The spatial resolution in the depth direction was evaluated experimentally to be approximately 1 mm. Our results show that the system could have applications in industrial fields.