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WITH ATOMIC PRECISION
In 1955 Strojnik designed and constructed
his first electron microscope in Ljubljana, the
LEM1, making Yugoslavia the fifth country in the
world to have its own electron microscope and
one that was the product of domestic know-
-how. In the subsequent years, the Electron Mi-
croscopy Laboratory, which Strojnik established
and led at the Faculty of Electrical Engineering,
would produce a series of electron microscopes,
named LEM1 to LEM4. The latter, which was pro-
duced by the company Iskra, was the first such
device in the world to be air-cooled.
Electron microscopes have a higher resol-
ving power than optical microscopes, whose re-
solution is limited by the wavelength of visible
light to 0.4-0.7 thousandths of a millimetre. As
a source of illumination, electron microscopes
use a beam of accelerated electrons, which, in
accordance with the laws of quantum physics,
behave like waves. Due to the mass of electrons,
such waves have wavelengths up to 100,000 ti-
mes shorter than visible light, making it possi-
ble to detect individual atoms.
TEACHING
Strojnik was considered an exceptional tea-
cher and lectured at the Faculty of Electrical En-
gineering between 1950 and 1969. He believed
that teaching was an important duty for every
professor, which also motivated him to write
textbooks for all the subjects he taught. His bo-
oks on aviation, including popular science titles
and expert works, are considered superb.
Literature:
Aleš Strojnik, Marija Scholl, Physics Today, May 1997.
Sandi Sitar, 100 slovenskih znanstvenikov, Ljubljana, 1987.
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