A History of the First North American Electron Microscope

Abstract

North America's first Transmission Electron Microscope -- and the first of immediate practical application anywhere -- was designed by two graduate students in the Department of Physics at the University of Toronto over the 1937-38 Christmas holidays and was built during the first four months of 1938. By April it produced consistently promising micrographs and before the end of the year, demonstrated magnifications of 20,000 diameters with resolution better than 140Å. The resolving power had been pushed to less than 608. (30 atom diameters) within another ten months. The design of this microscope was adopted by the Radio Corporation of America and developed into the prototype of a commercial series. It was this RCA production model, based directly on the Toronto microscope, that was the equipment selected by laboratories throughout the world for a generation. This represented an extraordinary achievement for the two young Canadians: Albert Prebus and James Hillier.