The development of electron microscope in the early 1930s in Germany had been watched with keen interest by scientists in Japan. In order to promote studies of electron microscopy and its applications more comprehensively, the need for a research committee was strongly promoted by Prof. S. Seto, Tokyo Imperial University and others. Thus a committee, the 37th Subcommittee of the 10th committee of the Japan Society for the Promotion of Science, was started May 1939 in Tokyo, gathering active researches. Development of electron microscopes in Japan was started by members of this subcommittee.

Hitachi was one of the original members of the subcommittee. The first Hitachi transmission electron microscope (TEM) model HU-1 was developed in 1940. In 1942, Hitachi delivered the first Japanese commercialized TEM model HU-2 to Nagoya Imperial University just at the height of the Second World War. Although difficulties caused by the war became harder, research and development activities were continued. After the war was over, developments accelerated. In 1953, the first export of Hitachi TEM was accomplished and in 1958 the model HS-6 was awarded Grand Prix in the Brussels Exposition.

JEOL was founded in 1949, and TEM model JEM-1 was developed. JEM-5A, sold in 1953, adopted a two-stage illumination lens system and a three-stage imaging lens system, which enabled observation of not only the TEM image, but also the electron diffraction pattern. As a result, the usage has expanded not only to researchers in the field of biology and medicine, but also to those in the field of materials science. The JEM-5G, which was released in 1956, was exported to France for the first time. This was the first step of JEOL overseas expansion. With JEM-7, sold in 1964, electron beam deflectors and electromagnetic astigmatism correctors were built in, and since then, mechanical operation of alignment and astigmatism correctors were changed to electromagnetic operation, and thus TEM operation was greatly improved. Japanese TEMs achieved a significant increase in market share in the 1960s.