Development of a high-speed camera system for neutron imaging at a pulsed neutron source

A neutron energy resolved imaging system with a time-of-flight technique has been newly developed and installed at Japan Proton Accelerator Research Complex (J-PARC) with the aim to investigate more preciously and rapidly a spatial distribution of several elements and crystals in various kinds of materials or substances. A high-speed video camera (CMOS, 1300 k frame/s) equipped system allows to obtain TOF images consecutively resolved into narrow energy ranges with a single pulsed neutrons while conventional CCD camera imaging system could obtain only one TOF image in an arbitral neutron energy region in the pulsed neutron energy region from 0.01 eV to a few keV. Qualities of the images obtained with the system, such as spatial resolution (defined by modulation transfer function, 0.8 line-pairs/mm at En∼0.01 eV), dependence of the brightness on the neutron energy and measurement errors (∼2%) of the system were examined experimentally and evaluated by comparison with those of conventional imaging system. The results obtained in the experiments show that the system can visualize the neutron energy resolved images within a small error even at high speed.