Abstract:The prompt gamma activation imaging technique is based on prompt gamma-ray neutron activation analysis, combined with collimation or associated particle measurements to realize the measurement of the position distribution of the elements inside the sample. Currently, most of the related researches are carried out based on large neutron sources, which limits the application scenarios of this technique, and the mobile miniaturized neutron source is an inevitable requirement for the field application of this technique. The prompt gamma activation imaging technique based on the movable neutron source can be divided into three categories according to the collimation method, which are based on single-hole collimation, coded-hole collimation, and accompanying particle measurement, and this paper introduces and discusses the technical principle, research progress, and the problems that still exist. The spatial resolution still needs to be improved. In the future, it will be further combined with image processing algorithms to improve the imaging quality and reduce the measurement time.