A STUDY ON THE DEVELOPMENT OF A FAST-NEUTRON TELEVISION CONVERTER

Experiments on fast neutron radiography (FNR) were carried out using the fast neutron source reactor YAYOI of the University of Tokyo. For a real time imaging technique using FNR, for a fast neutron television system (FNR-TV), it is essential to develop a highly sensitive luminescent converter in order to obtain good quality images. A new converter was recently developed and tested. It showed an about six times higher sensitivity compared with the first prototype converter. In this paper, the characteristics of the converter are discussed as well as the clearer images of a FNR-TV when using the converter. The FNR-TV images were obtained with 500 frames integrated. A small hole (1.0 mm in diameter and 10 mm in depth) in an acrylic plate was well imaged through a 50 mm thick iron block. A 0.15 mm thick aluminum spacer in the calibrated fuel pin was also discernible.