Ernst Ruska (1906-1988)

Ernst Ruska was born on December 25 ,1906 in Heidelberg to parents Professor Julius Ruska and his wife Elisabeth. And died at the on May 25, 1988. He was the fifth of seven children that they had. In 1925, after he graduated from grammar school in Heidelberg, he went on to study electronics at the Technical Collage in Munich, and two years later furthered his studies in Berlin. During his schooling he got some practical training from Brown-Boveri & Co in Mannheim and Siemens & Halske Ltd in Berlin. When he was still in school he also began his involvement with high voltage and vacuum technology at the Institute of High Voltage, under the supervision of Dr Max Knoll. Along with his help and other doctoral students he worked on the development of a high performance cathode ray oscilloscope.

He completed his first scientific work during 1929, which was concerned with the mathematical and experimental proof of Busch’s theory of the effect of the magnetic field of a coil of wire through which an electric current is passed and which is then used as an electron lens. Through this intensive study he recognized that focal length of waves could be shortened by the use of an iron cap, form this discovery the polschuh lens was developed, a lens used in all magnetic high-resolution electron microscopes.

In 1931 he and Dr Knoll constructed the first electron microscope, with this instrument two of the most important processes for image reproduction were introduced- the principles of emission and radiation. In 1933, Ruska was able to put into use an electron microscope, that for the first time gave better definition than a light microscope. During his Doctoral thesis of 1934 and for his university teaching thesis (1944) at the Technical College in Berlin, he continued to investigate the properties of electron lenses with short focal lengths.

Since further technical development of electron microscopes could not be financially supported by the university, Ruska went to work in the field of electron optics. From 1933-1937 he worked with Fernseh Ltd in Berlin-Zehlendorf and was responsible for the development of television receivers and transmitters, and well as photoelectric cells with secondary amplification. During this time he continued to develop a high-resolution electron microscope because he was convinced that is had great practical importance for applied and pure research.

In 1939 the first customized electron microscopes ( the ‘Siemens Super Microscope’). At the same time his brother, Dr Med. Helmut Ruska, and his colleagues worked on it’s application in the medical and biological fields. In 1940, a visiting institute was set up to demonstrate the use of the microscope by Siemens & Halske. From this institute Ruska worked with both German and foreign scientists, and about two hundred scientific papers were published before the end of 1944. His task from now on was the development and production of electron microscopes, and around the beginning of 1945, 35 institutions were equipped with one.

In the years following 1945, along with some new colleagues, reconstructed the Institute of Electron Optics in Berlin-Siemensstadt, which had been disbanded due to bomb, and in 1949 electron microscopes were being built again. At the same time he sought further physical development of the electron microscope by working at other scientific institutions. From August 1947 to December 1948 he worked at the German Academy of Sciences in Berlin, in the faculty of Medicine and Biology, then from January 1949 as head of department at what is today the Fritz Haber Institute of the Max Planck Society in Berlin-Dahlem. On June 27, 1957 he was made Director of the Institute for the Electron Microscopy, and retired on December 31, 1974.

Because of his great contribution to science thanks to the Scanning Electron Microscope, Ernst Ruska was awarded the Nobel Prize in Physics in 1986.