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Transmisssion electron microscope Tesla BS500 |
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| Year of manufacture: | 1990 |
| Manufacturer: | Tesla Brno |
| Description: |
The transmission electron microscope works on a principle similar to the traditional glass TV picture tube. It consists of a hermetically sealed chamber. On the top of the chamber, there is an electron gun connected to a source of approx. 100 kV. An electron ray comes out of the gun. In the middle of the chamber, the examined specimen is placed. The ray goes through the specimen and is partially absorbed. Then the ray impacts on a fluorescent screen which is placed in the bottom of the chamber. The screen is watched through a window with an ordinary optical microscope. It is necessary that the specimen is very thin, in the order of nanometers. After the specimen is placed into the chamber, a mercury pump creates vacuum inside the chamber, so the electrons can pass freely through. The ray has a much smaller wavelength than visible light and thanks to this, very large magnification is possible. The ray is shaped with electrostatic or electromagnetic lens.
Electron microscopes are still produced in Brno up till today. |
