THANK YOU, TIM Palucka, for “Making the Invisible Visible” (Winter 2002), with its stunning illustrations and its previously unpublished reminiscences from James Hillier and others. I have two observations.
First, neither Reinhold Rudenberg—my father— nor Ernst Ruska began his work toward the electron microscope with knowledge of the concept of electron waves and their much smaller wavelength than that of visible light. Rudenberg conceived his microscope, in 1930-31, on the premise that the small size of electrons would enable them to surpass the resolution of a light microscope. And Ruska began not with the goal of a microscope but wanting to confirm experimentally the lens formulas proposed by Hans Busch, who had first described the focusing properties of magnetic coils surrounding an electron beam. Only subsequently did the two engineers realize what physicists had known since 1923: that the minute wavelength of accelerated electrons was the key to higher resolution.
Second, early workers in the field received many awards, and in a ceremony in July 1941, Theodor Vahlen, president of the Berlin Academy of Science, wearing his black SS major general’s uniform, presented the 1941 Leibniz medal to Ruska, Bodo von Borries, and others for their contributions to the electron microscope. By then Rudenberg had left Germany for the United States. In 1946 he received the Stevens Honor Award from the Stevens Institute of Technology for his role in the invention.
H. Gunther Rudenberg
SCARBOROUGH, ME.
