General view of two technicians using a RCA Model EMU electron microscope in the Dow Chemical Company's Metallurgical Laboratory. Electron microscopes use a beam of accelerated electrons as a source of illumination and have a higher resolving power that, in contrast to light microscopes, can reveal the structure of smaller objects.

Notably, the Model EMU debuted in 1944 and was the first American-manufactured RCA electron microscope capable of both imaging and electron diffraction.