Posted by: Glow-worm PJ22 MAY 2013
Today, 25 May 2013, marks the 25th anniversary of the death of the German physicist Ernst Ruska. He was awarded the Nobel Prize for physics in 1986 for his work on electron optics, including the design of the first electron microscope.
Ruska was born on 25 December 1906 in Heidelberg. After finishing grammar school he studied electronics at the technical college in Munich, before moving to Berlin, where he became involved in the study of high voltage and vacuum technology, under the direction of Max Knoll.
He worked on the development of the cathode ray oscilloscope, dividing his time between the development of materials to construct vacuum instruments, and the theory and practical experiments into the optical behaviour of electron rays.
Magnification in traditional microscopes is limited by light’s wavelength, and Ruska postulated that much greater magnification could be achieved by using electrons, with wavelengths 1,000 times smaller than light.
Ruska’s first completed work was on the mathematical and experimental proof of Busch’s theory, which suggested that the magnetic field generated in the short coil of a cathode ray tube made charged electron particles behave in a way similar to light passed through a convex glass lens.
It was his development and application of these discoveries that led to the production of the first electron microscope in 1933.
By 1937 Ruska was working for the Siemens Company where, in 1939, he was responsible for the development of the first commercially produced electron microscope. He encouraged Siemens to set up a laboratory for visiting researchers, to develop the use of his microscope in medical and biological applications.
By 1945, 35 institutions were using one of his microscopes, and his work culminated in the production, in 1954, of the Elmiskop 1, which was used in over 1,200 sites around the world.
In June 1957 Ruska was made director of the Institute of Electron Microscopy, a post he held until his retirement on 31 December 1974.