Days of Electron
11.-15. 3. 2020
[ Pictured: vine leaf ]

a Brno

Electron microscopy has been associated with Brno since 1951.
Nowhere else in Europe is there such a concentration of companies and scientific institutes dealing with this discipline as in Brno.
Electron microscopes can magnify the object up to 1,000,000 times
Under an electron microscope scientists also study viruses such as HIV, ZIKA and SARS.
More than 700 electron microscopes are manufactured in Brno every year
The average price of an electron microscope is about CZK 20 million
Ernst Ruska commissions the first electron microscope at the Institute of Technology in Berlin (for which he later wins the Nobel Prize in 1986)
The first two electron microscopes come to Czechoslovakia from the USA as part of the post-war aid from the international organisation UNRRA
The first Czechoslovakian commercially available electron microscope – the Tesla BS 241 – is developed in Brno
The Institute of Scientific Instruments of the Czech Academy of Sciences was founded
The Tesla BS 242 electron microscope wins a gold medal at the EXPO 1958 world exhibition in Brussels
Founding of the companies TESCAN, Delong Instruments and Delmi (nowadays Thermo Fisher Scientific), producing electron microscopes in Brno
Almost 35% of the world's electron microscope production is manufactured in Brno


What are electron microscopes used for?
Electron microscopes shift the boundaries of human knowledge in many fields; they are used mainly in medicine, research into materials, the aerospace, automotive and semiconductor industries, criminology and the mining of minerals. Electron microscopes are an indispensable aid in the production of new chips, thanks to which mobile phones, tablets or computers are more powerful. They have also been used in battery development.

What is the difference between an optical and an electron microscope?
While the optical microscope uses rays of light for imaging, electron microscopes replace light with electrons and use electromagnetic lenses instead of glass lenses. And because the wavelength of the electrons is significantly shorter than that of visible light, the electron microscope also has a higher resolution, resulting in much higher effective magnification than with an optical microscope. The approach is comparable to the idea that you are looking at the earth from the moon and you can also distinguish the leaves on the trees. With the help of electron microscopes, scientists can observe samples with a resolution of billionths of metres.

Why does the electron microscope show only black and white?
The electron microscope does not work with light, but with electrons, so all images are in shades of gray. Subsequently, they can be coloured manually or with the use of an automatic programme.

What types of electron microscope exist?
There are two types of electron microscope – the transmission electron microscope (TEM) and the scanning electron microscope (SEM). In a transmission electron microscope, electrons pass through the observed sample and are then detected. It is necessary to use thin samples and high energies so that electrons can pass through the observed object. On the other hand, the thickness of the sample does not play a role in the case of scanning electron microscopes, because the surface of the sample is displayed using secondary or backscattered electrons.

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