ABSTRACT
Ion accelerators first appeared around 1930 and began growing rapidly in the 1930s. At the beginning of the growth period, the ion accelerators were originally designed as experimental equipment required for nuclear physics and for radioisotope production. A variety of ion accelerators has so far been developed in succession to meet the demands from nuclear research. The beginning of the ion beam applications, except for nuclear research, was the medical application to the treatment of tumors with charged particles started in the 1950s. For industrial applications of ion accelerators, ion implantation began in the middle of the 1960s. The use ofion beams for material analysis became widespread in the 1970s. The full-scale applications of MeV ion beams to materials, bio-, medical, and life sciences have rapidly broadened in the 1990s.
