Ernst Ruska

Über eine Berechnungsmethode des Kathodenstrahloszillographen auf Grund der experimentell gefundenen Abhängigkeit des Schreibfleckdurchmessers von der Stellung der Konzentrierspule. Studienarbeit Technische Hochschule Berlin, Lehrstuhl für Hochspannungstechnik, eingereicht am 10.5.1929.

On a method of designing a cathode ray oscillograph on the basis of of the experimentally found dependence of the writing spot diameter on the position of the concentration coil. Student project thesis, carried out in the High Voltage Laboratoty of the Technische Hochschule Berlin, submitted May 10, 1929.

The student project thesis was the first step. This project ogether with the diploma project of 1930 - "Untersuchung elektrostatischer Sammelvorrichtungen als Ersatz der magnetischen Konzentrierspulen beim Kathodenstrahloszillographen." (2) - was the theoretical and practical basis for the coming develeopment of the electron microscope, reaching in the late 1933/1934 at the first time a greater magnification than the best light microscopes and starting with the name of "Ultramicroscope" its way to scientific breakthrough.

"Studienarbeit" contents:

  • 2 cover pages
  • 1 main title
  • 2 index pages
  • 84 text pages
  • 14 spreadsheets/diagrams (blueprints), 1 in the format DIN A3
  • 6 picture pages
  • 20 drawings
  • several formulas/calculations


  • The facsimile scans have a format of 500 x 687 pixel at 72 dpi. The thumbnail-index of "Studienarbeit" contains german terminology - but is simple to translate:
    • "S" = "Seite" = page
    • "Inhalt" = index
    • "Text" = text
    • "Bild" = picture
    • "Fig." = "Figur" = drawing
    • "Formel" = formula
    • "Blau" = "Blaupause" = blueprint

    The index pages contain active links to related text pages. * bibliothek * 001 * Studienarbeit (1928)